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Ice & Water Shield Requirements by Jurisdiction
What each jurisdiction’s own sources say about ice barrier (ice & water shield) on residential re-roofs — the conditions are the value. Adjacent cities contradict each other (Denver’s own climate table says No while Aurora’s says Yes), some counties gate the requirement by elevation (above 7,000 ft under Douglas County and the Pikes Peak Regional Building Code), and many cities defer entirely to shingle-manufacturer instructions. The regional split is stark. Every Dallas–Fort Worth authority we checked fills in “No” in its own amended IRC Table R301.2(1) climate criteria — north Texas has no ice-damming history to design for. Kansas splits down the middle of the state: the Kansas City–side suburbs (Overland Park, Olathe, Lenexa, Leawood, Johnson County) all require an ice barrier 24 in. inside the exterior wall line, while Wichita, Sedgwick County, Derby, Haysville, Butler County, Topeka and Shawnee County all answer “None Required” in their own adopted tables. Two roofs 150 miles apart in the same state, opposite answers. Oklahoma works differently again: a statewide amendment (OUBCC, §905.1.2) requires a 36-inch ice barrier in ALL valleys and at ALL changes in roof pitch where the lower roof is shallower — unconditionally, everywhere in the state — on top of whatever each city says about eaves. So in Oklahoma the honest answer is usually “yes in valleys, maybe not at eaves.” Missouri splits the same way Kansas does, east to west: every Kansas City-side jurisdiction we cover answers “Yes” (Kansas City, Independence, Lee’s Summit, Blue Springs, Liberty, Gladstone, Raytown, Grandview, Grain Valley, Belton, North Kansas City, Clay County, Cass County), while every St. Louis-side jurisdiction answers “No” — the City of St. Louis wrote “Ice Shield Underlayment Required: Not Required” into its own amended Table R301.2(1), an explicit decision rather than silence. So the KC metro agrees with itself across the state line while both Kansas and Missouri disagree with their own other halves. Nebraska is the most uniform state we cover: every Omaha/Lincoln-area jurisdiction checked answers “Yes.” The short version for a roofer working the hail belt: assume an ice barrier around Kansas City, assume none in north Texas or around Wichita and St. Louis, and read the card before you bid anywhere in between. Only jurisdictions with an explicit sourced statement appear here. The narrative version, including Colorado’s 7,000-foot elevation gate and Oklahoma’s statewide valley rule, is in the guide: theroofingbook.com/guides/where-code-requires-an-ice-and-water-barrier/.
What the requirement is asking for: Ice and Water Barrier — the material reference, with the governing standard.
Ice barrier required — Colorado (146)
Alamosa County Building Department (Alamosa County, Colorado)
Alamosa County's Table R301.2(1) exhibit lists "Ice barrier underlayment required: YES" as the county's completed determination for unincorporated Alamosa County.
Archuleta County Building Department (Archuleta County, Colorado)
Archuleta County's 2019 building-code resolution (recorded 9/6/2019, reception no. 21905098), Section 2(c) completing IRC Table R301.2(1), prints "Ice Shield Underlayment Required – Yes."
Boulder County - Community Planning & Permitting (Boulder County, Colorado (unincorporated))
County climatic/geographic design-criteria table: "ICE BARRIER UNDERLAYMENT REQUIRED = YES. In accordance with Sections R905.1.2, R905.4.3.1, R905.5.3.1, R905.6.3.1, R905.7.3.1 and R905.8.3.1, where there has been a history of local damage from the effects of ice damming, ice barrier is required." Boulder County's official determination applies this trigger countywide (no elevation threshold).
Central City - Building, Historic Preservation and Planning (City of Central City, Colorado)
Central City Municipal Code § 18-1-20(c) item (7), Table R301.2(1) as filled: "Ice Barrier Underlayment Required: Yes."
Chaffee County Building Safety Department (Chaffee County, Colorado)
Chaffee County Ordinance 2023-02, Exhibit B, amended Table R301.2(1) prints "Ice Barrier Underlayment Required: Yes, per 2021 International Residential Code R905.1.2" as part of the county's climatic and geographic design criteria.
City of Alamosa - Building Department (City of Alamosa, Colorado)
Alamosa's amended IRC Table R301.2(1) (Alamosa Municipal Code § 4-21(2)) lists "Ice barrier underlayment: Yes" as the city's completed determination.
City of Aspen Building Department - Community Development (City of Aspen, Colorado)
Aspen's amended IBC Table 1601.2 (Sec. 8.20.020 item ww) prints "Ice Barrier Underlayment Required = Yes" as the citywide determination (this table is the functional equivalent of IRC Table R301.2(1); Aspen deleted the IRC, per Sec. 8.16.010). The mandate is also stated as operative statute text at Sec. 8.20.020 item uu, amending IBC Sec. 1507.1.2 Ice Barrier: "an ice dam barrier that consists of at least two (2) layers of underlayment cemented together or of a self-adhering polymer modified bitumen sheet shall be used in lieu of normal underlayment and shall extend from the roof eave edge at least six (6) feet inside the exterior wall line as measured along the roof surface, eighteen (18) inches from the centerline of the valley and up twenty-four (24) inches on the vertical wall at a roof and wall juncture."
City of Aurora - Building Division (City of Aurora, Colorado)
City of Aurora Engineering Design Criteria (Public Works Building Division Form #A200, rev. 01/2022, for the 2021 I-Codes) lists "Ice Barrier Underlayment Required: Yes" for the city; per the unamended IRC R905.1.2 baseline this extends from the eave edge to 24 in. inside the exterior wall line on all eaves.
City of Black Hawk - Building Division (City of Black Hawk, Colorado)
Black Hawk Municipal Code § 18-6 item (9), Table R301.2(1) as amended: "Ice Barrier Underlayment Required: Yes."
City of Brush Community Development Department (City of Brush, Colorado)
IRC Table R301.2(1) as filled in by item (8) of Brush Municipal Code § 18-3-30 (Amendments to the International Residential Code, 2018 IRC): "Ice Shield Underlayment Required Yes". The same printed table leaves the Wind Speed, Topographic effects, Special Wind Region, and Windborne Debris Zone cells blank (see wind_design_criteria — left ABSENT for that reason).
City of Centennial - Building Division (City of Centennial, Colorado)
"Ice barrier underlayment water shield is a requirement on all roofs" - stated as a blanket requirement in the city's Residential Roof Repairs and Re-Roofing policy, not limited to eaves only.
City of Cherry Hills Village Building Department (City of Cherry Hills Village, Colorado)
The City's printed Table R301.2 (continuation image) on the Adopted Building Codes page lists "Ice Barrier Underlayment Required: Yes." The City's separate "Specific Roofing Requirements" guide states, under "Ice Dam Protection": "Cherry Hills Village has a history of ice damming in the past. Therefore, in accordance with IRC Section 301.2 an ice barrier is required to be installed in lieu of the regular underlayment and extend from the lowest edges of all roof surfaces in accordance with the above code sections."
City of Commerce City - Building Inspection Division (City of Commerce City, Colorado)
City of Commerce City's locally amended Table R301.2 "CLIMATE GEOGRAPHIC DESIGN CRITERIA" states "Ice barrier underlayment required: Yes" citywide, which triggers the unamended IRC R905.1.2 baseline: ice barrier extends from the lowest edges of all roof surfaces to a point at least 24 in. inside the exterior wall line. This is an adopted building-code requirement that applies even though most residential reroofs are exempt from needing a permit.
City of Cortez - Building Division (City of Cortez, Colorado)
City of Cortez Ordinance No. 1249, Series 2018, Section 2(i) amends Table R301.2(1) to insert "Ice Underlayment Required: Yes." The City's "Building Codes & Design Standards" webpage republishes the same line as "Ice Barrier Underlayment Required: Yes."
City of Craig - Craig/Moffat Regional Building Department (City of Craig, Colorado)
Craig Municipal Code § 15.06.066 (Table R-301.2(1) fill-in, Ord. 1088 §1, 2019): "Ice barrier underlayment required: Yes."
City of Cripple Creek Building Department (City of Cripple Creek, Colorado)
Cripple Creek Municipal Code § 18-4-20's amended Table R301.2(1) prints "ICE BARRIER UNDERLAYMENT REQUIREMENT ... Yes" as one of the added climatic design criteria rows.
City of Dacono - Community Development Department (Building Division) (City of Dacono, Colorado)
Guide states "ICE AND WATER SHIELD IS REQUIRED ON ALL ROOFS" (Wind/Weather Resistance section) — stated as a blanket requirement with no eave-distance or slope condition given.
City of Durango - Building Division (City of Durango, Colorado)
Durango's amended IRC Table R301.2 (§ 6-144) lists "Ice barrier underlayment required: YES" in its own unambiguous single-column cell.
City of Edgewater Building Division (City of Edgewater, Colorado)
Edgewater's own amendment to IRC Table R301.2, Municipal Code Section 18-3-30(6), requires an ice barrier underlayment, which triggers Section R905.1.2's ice-barrier-installation mandate for asphalt shingles and other covered roof types.
City of Englewood - Building Division (City of Englewood, Colorado)
Ice and water shield is required to extend 24 inches inside the exterior wall line of the building.
City of Evans - Building Division (City of Evans, Colorado)
Evans Municipal Code § 15.09.010's fill-in of IRC Table R301.2(1) prints "Yes" in the "Ice barrier Underlayment Required" column.
City of Fort Collins - Building Services (City of Fort Collins, Colorado)
2024 IRC R905.1.2 (unamended, adopted by City of Fort Collins): ice barrier required where Table R301.2 designates it (Fort Collins is designated "Required"); barrier must extend from the lowest roof edge to a point not less than 24 in. inside the exterior wall line (36 in. measured along the slope on roofs pitched 8:12 or greater).
City of Fort Lupton - Building Department (City of Fort Lupton, Colorado)
FAQ states "Yes, ice and water shield barriers & drip edge are required in the City of Fort Lupton" — stated as a blanket requirement; no eave-distance, slope, or elevation condition is given in the FAQ text.
City of Glenwood Springs - Building Department (City of Glenwood Springs, Colorado)
"Ice Barrier Underlayment Required: Yes" (IRC Table R301.2 as printed in City of Glenwood Springs Ordinance No. 06, Series of 2022, Title 060 § 060.030.020).
City of Golden - Building Division (City of Golden, Colorado)
Golden requires an approved ice barrier for all new and re-roofing applications; the barrier must extend from the lowest roof edge to a point no less than 24 inches inside the exterior wall line of the building (per handout: IRC 2024 R905.1.2 / IBC 2024 1507.1.2).
City of Greenwood Village - Community Development (City of Greenwood Village, Colorado)
An ice barrier membrane shall be installed at all eaves directly over the roof deck and extend at least 24 inches inside the exterior wall line. Detached accessory structures without conditioned floor area are exempt.
City of Gunnison Building Department (City of Gunnison, Colorado)
Required, and scoped to where ice dams form rather than across the whole deck. The City of Gunnison fills in the climatic and geographic design criteria table and answers the ice barrier underlayment row with "In roof valleys and eaves".
City of Idaho Springs Building Department (City of Idaho Springs, Colorado)
Idaho Springs Municipal Code § 19-15 item (G), Table R301.2(1) as filled: "Ice Shield Underlayment Required: YES."
City of Lafayette - Building Division (City of Lafayette, Colorado)
Ice and watershield is required (including the eaves and valleys).
City of Lamar Building Department (City of Lamar, Colorado)
"Ice barrier underlayment required Yes" -- IRC Table R301.2 as filled in by Sec. 6-184(a)(7), Amendments to the 2018 IRC (Lamar Municipal Code).
City of Leadville Building Department (Lake County Community Planning & Development) (City of Leadville, Colorado)
Leadville's printed Table R301.2(1) (§ 15.04.030(19)) carries "Ice Barrier Underlayment Required: Yes." Separately, § 15.04.030 items (35)-(41) amend IRC Sections R905.2.7, R905.3.3, R905.4.3.1, R905.5.3.1, R905.6.3.1, R905.7.3.1, and R905.8.3.1 (the material-specific ice-barrier clauses) in identical, universally-applicable language: "In lieu of normal underlayment, an ice barrier that consists of at least two layers of underlayment cemented together or a self-adhering polymer modified bitumen sheet, shall extend from the edge of the eave to a point at least seventy-two (72) inches inside the interior wall line of the building. All valleys shall have at least one (1) thirty-six (36) inch-wide layer applied and shall extend eighteen (18) inches from centerline each way."
City of Littleton - Building and Code Compliance Division (City of Littleton, Colorado)
Ice and water barrier underlayment complying with ASTM D1970, extending a minimum of 2 feet inside the exterior wall line, is required at eaves of all conditioned structures. In valleys: closed valleys require ice and water barrier underlayment at least 36 inches wide; open valleys require one 24-inch-wide galvanized metal layer, or two layers of mineral-surfaced rolled roofing (18 in. and 36 in. wide). Double underlayment or ice and water barrier underlayment is also required where asphalt shingles are installed on a 2/12-4/12 pitch roof.
City of Longmont - Building Inspection Division (City of Longmont, Colorado)
The City of Longmont does require Ice & Water Shield. Manufacturer's installation instructions and code must be followed; where in conflict the more restrictive applies. Roof slopes between 1/12 and 2/12, above non-habitable space, are permitted to use a bituminous membrane (ice and water guard) then asphalt shingles.
City of Louisville - Building Safety Division (City of Louisville, Colorado)
CARRIED FROM A SOURCE THE CITY HAS REMOVED. The finding (ice barrier required, verified at mid-roof inspection against ASTM D1970 and IRC R905.1.2) came from the City's "Roofing Update and Guidelines" page, deleted in the 2026 site rebuild, and no live City document re-establishes it. The adopting ordinance cannot: Ordinance No. 1907, Series 2025 revises Table R301.2(1) only by pointing at the ASCE hazard tool for loads and publishes no ice-barrier designation, and R905.1.2 conditions the requirement on exactly that table entry. Left as TRUE rather than flipped, because an absent designation is not evidence that no ice barrier is required and Louisville sits in a climate where one ordinarily would be -- but it is unverified and must not be treated as a sourced affirmative until a reader settles it.
City of Loveland - Building Division (City of Loveland, Colorado)
Required on all eaves, installed over the required metal drip edge; not less than 24 in. inside the exterior wall line (36 in. inside for roofs greater than 8:12 pitch).
City of Manitou Springs Planning Department (permits via PPRBD) (City of Manitou Springs, Colorado)
Conditional on elevation, not universal: Section RBC303.4.2 of the 2023 Pikes Peak Regional Building Code prints "Ice Barrier Underlayment Required ... YES" in Table R301.2, with footnote d: "Required only for buildings and structures with a grade plane at or above 7,000 ft (2,134 m) elevation." Manitou Springs sits below 7,000 ft, so this table cell is conditional for most construction in the city (same regional determination documented for the Pikes Peak Regional Building Department itself).
City of Montrose - Building Services (City of Montrose, Colorado)
Montrose Code of Ordinances § 4-1-3(4)'s printed Table R301.2(1) carries the row "ICE BARRIER UNDERLAYMENT REQUIRED" with the printed value "YES."
City of Ouray Community Development - Building Services (City of Ouray, Colorado)
Required city-wide. The City of Ouray's substituted climatic and geographic design criteria table answers "Ice Barrier Underlayment" with "Yes", so the ice barrier provisions of the adopted residential code apply to every roof in the city.
City of Rifle Building Department (City of Rifle, Colorado)
"Ice Shield Underlayment Required Yes" -- IRC/IBC Table R301.2(1) as filled in by Rifle Municipal Code Sec. 18-2-30(3) (Amendments to the 2015 IBC), applied to the Residential Code via Sec. 18-3-30(2).
City of Salida Community Development Department (City of Salida, Colorado)
Required city-wide. The City of Salida amends the climatic and geographic design criteria table, and that table answers "Ice Barrier Underlayment Required" with "Yes, per 2021 International Residential Code R905.1.2".
City of Sheridan Building Department (City of Sheridan, Colorado)
Table R301.2 as amended by § 18-3(j) prints "Ice Shield Underlayment required: Yes." This corroborates the City's own Roofing Requirements page, which independently states: "Ice and water barrier is required on lower roof eaves. The membrane must be installed a minimum of 24" inside the heated space. Unheated areas are exempt."
City of Steamboat Springs - Routt County Regional Building Department (City of Steamboat Springs, Colorado)
City of Steamboat Springs Building Code Ordinance, Sec. 5-5, Table R301.2(1) as amended: "Ice Shield Underlayment Required – Yes per IRC Section R905.1.2 Ice Barriers."
City of Trinidad - Building Department (City of Trinidad, Colorado)
Trinidad's amended IRC Table R301.2 (§ 5-2) lists "Ice barrier underlayment required: Yes" as the city's completed determination.
City of Victor - Building Department (City of Victor, Colorado)
Victor Municipal Code § 18-2-30, item 11's amended Table R301.2(1) prints "Ice Barrier Underlayment Required" as "Yes."
City of Wheat Ridge - Building Division (City of Wheat Ridge, Colorado)
"Ice and Water shield is required at eaves and shall extend a minimum of two (2) feet inside exterior walls."
City of Woodland Park Planning & Building Department (City of Woodland Park, Colorado)
Pikes Peak Regional Building Department's Reroof Guidelines handout states: "Elevations of the property is listed on the permit receipt. Properties that are above 7,000 ft. elevation require an ice barrier to be installed. This barrier shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering, polymer-modified bitumen sheet, and shall extend from the eave's edge to a point of at least 24 inches inside the exterior wall line of the building. (See 2023 PPRBC section RBC303.4.2 Table R301.2 footnote D and 2021 IRC section 905.1.2)" This is elevation-tiered, not a flat regional requirement -- required above 7,000 feet elevation, not required below it; Woodland Park's own townsite sits above that line.
City of Wray - Building Department (City of Wray, Colorado)
Table R301.2's Ice Barrier Underlayment row cross-references R905.1.2 rather than stating Yes/No directly. Ordinance No. 646 replaces R905.1.2 in full: "On roofs with a slope equal to or less than four units vertical in 12 units horizontal (33-percent slope), an ice barrier shall be installed for asphalt shingles, metal roof shingles, mineral-surfaced roll roofing, slate and slate-type shingles, wood shingles and wood shakes. The ice barrier shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet shall be used in place of normal underlayment and extend from the lowest edges of all roof surfaces to a point not less than 24 inches (610 mm) inside the exterior wall line of the building." This removes the base 2018 IRC's "history of local damage" trigger, making the ice barrier an unconditional requirement for qualifying roof coverings at or below a 4:12 slope.
Clear Creek County Building Department (Clear Creek County, Colorado)
Resolution R-26-19, Table R301.2(1) as amended: "ICE BARRIER UNDERLAYMENT REQUIRED: Yes." Applies to unincorporated Clear Creek County.
Conejos County Land Use Office (Conejos County, Colorado)
The county's printed Table R301.2(1) attachment ("CONEJOS COUNTY, COLORADO ATTACHMENT A") lists the "ICE BARRIER UNDERLAYMENT REQUIRED" column value as "YES."
Craig/Moffat Regional Building Department (Moffat County) (Moffat County, Colorado)
The Craig/Moffat Regional Building Department's Design Criteria page prints, as a row of the jointly-adopted Table R-301.2(1), "Ice barrier underlayment required: Yes."
Douglas County - Building Division (Douglas County, Colorado (unincorporated))
"Ice barrier underlayment is required for elevations above 7,000 feet. Ice barrier shall extend from the lowest edge of all roof surfaces to point at least 24 inches inside the exterior wall line of the building." Not required at elevations of 7,000 feet or below per the same FAQ (elevation-conditional, not universal).
Elbert County Building Department (Elbert County, Colorado)
"Per Ordinance 22-01: Ice Barrier shall be installed for asphalt shingles, metal roof shingles, mineral-surfaced roll roofing, and slate and slate-type shingles." (called out in a red highlight box specific to Elbert County within the county's Single Family Residential Re-roofing guide). Corroborated by the county's Mid/Final Roof Declaration, which requires the installer to declare: "Ice and water shield is installed at eaves, 24" inside the heated wall on all heated buildings in consideration of pitch, buildings attached to heated buildings and buildings with habitable space, per section R905.1.2 of the 2018 IRC Building Code. 90lb felt, or equivalent, or valley metal is installed in valleys."
Fremont County Building Department (Fremont County, Colorado)
Resolution No. 60, Series of 2020, amends Table R301.2(1) of the adopted 2018 IRC for unincorporated Fremont County; the printed cell reads "Ice barrier underlayment required — Yes."
Garfield County Community Development Department (Garfield County, Colorado)
"ICE SHIELD UNDER-LAYMENT REQUIRED -- Yes." (Table R301.2(1) as amended by Garfield County Building Code Resolution of 2017, Resolution No. 2017-23, Exhibit A, Sec. R301 amendment; corroborated by the county's "Building Requirements -- Residential Projects" summary sheet: "Ice Barrier Underlayment: Required.") This is a county-wide requirement, not elevation-tiered like the snow load figures.
Grand County Building Division - Community Development (Grand County, Colorado (unincorporated))
Grand County's Table R301.2(1) amendment prints "ICE BARRIER – YES" as one of the added design-criteria rows. Section R905.1.2 is separately amended to read: "AN ICE BARRIER THAT CONSISTS OF AN APPROVED SELF-ADHERING POLYMER MODIFIED BITUMEN SHEET SHALL BE USED IN LIEU OF NORMAL UNDERLAYMENT ON ALL SLOPED ROOFS. THIS ICE DAM PROTECTION UNDERLAYMENT SHALL BE INSTALLED FROM THE EAVES TO A POINT 6 FEET (1829 mm) INSIDE THE EXTERIOR WALL OF THE BUILDING AND 24 INCHES (610 mm) FROM THE CENTERLINE OF ALL VALLEYS, FULLY ADHERED TO THE SUBSTRATE ON ALL HABITABLE STRUCTURES. Exception: Detached accessory structures not containing conditioned floor area."
Gunnison County Community Development - Building Office (Gunnison County, Colorado)
Gunnison County's Table R301.2 amendment (Resolution 23-22, Attachment B) prints "Ice Barrier Underlayment Required: Yes" as one of the added design-criteria rows.
Huerfano County Land Use and Building Department (Huerfano County, Colorado)
County Resolution 23-25, Section 7, amends IRC Table R301.2 (Climatic and Geographic Design Criteria) and, as printed in the resolution itself, that amended table adds an "Ice Barrier Underlayment Required" column reading "YES (apply to elevations above 6200 ft.)". This is a locally set table entry in the county's own adopted code, which turns on the base IRC's ice-barrier-membrane requirement (Section R905.1.2) for construction above that elevation across unincorporated Huerfano County.
Jackson County Building Inspector (Jackson County, Colorado)
Jackson County's amendment to the 2018 IRC, Section R905.1.2, repeals and reenacts the ice barrier requirement: an approved self-adhering polymer modified bitumen sheet must be used in lieu of normal underlayment on all sloped roofs, installed from the eaves to a point 6 feet inside the exterior wall line and 24 inches from the center line of all valleys, fully adhered to the substrate, on all habitable structures. Detached accessory structures with no conditioned floor area are excepted.
Jefferson County - Building Division (Jefferson County, Colorado (unincorporated))
"Ice barrier shall be installed for asphalt shingles, metal roof shingles, mineral-surfaced roll roofing, slate and slate-type shingles, wood shingles and wood shakes per R905.1.2. Concrete and clay tile per manufacturer's instructions R905.3.8." (2026 county roofing notice does not restate a specific inside-wall distance beyond the R905.1.2 citation.)
La Plata County Community Development Department - Building Division (La Plata County, Colorado)
La Plata County Code Sec. 18-36's Table R301.2 amendment prints "Ice barrier underlayment required" as one of the county's climatic design criteria. The County's own Building Permit Application Packet (revised 2/9/2024) independently lists "Ice barrier underlayment required" as its own bullet under "Climate and Geographic Design Requirements," matching the codified table.
Lake County Community Planning and Development (Lake County, Colorado)
Resolution 2026-20's Table R301.2 prints "Ice Barrier Underlayment Required" as "Yes." Separately, the Resolution's Chapter 9 Roof Assemblies section amends R905.1.2 to read, in relevant part, that "Lake County has" (replacing "areas where there has been") a history of ice forming along eaves, requiring an ice barrier that "shall extend from the lowest edges of all roof surfaces to a point at least" 72 inches (replacing the base code's 24 inches) "inside the interior wall line of the building," and adds that "all valleys shall have at least a 36-inch-wide layer applied and shall extend 18 inches from centerline each way."
Larimer County - Building Division (Larimer County, Colorado (unincorporated))
"Ice Barrier (required county-wide). An ice barrier shall consist of not fewer than two layers of underlayment cemented together or a self-adhering polymer-modified bitumen sheet and shall extend from the lowest edges of all roof surfaces to a point at least two feet inside the exterior wall." Exceptions: metal panel roofs, membrane roof coverings, and detached accessory structures with no heated floor area; existing asphalt shingles with no ice barrier may receive a second layer of roof covering without adding an ice barrier. No elevation threshold is stated — the requirement applies countywide regardless of elevation.
Las Animas County Building Department (Las Animas County, Colorado)
The county's design requirements document states plainly: "ICE BARRIER REQUIRED ABOVE 6,500 FEET" for unincorporated Las Animas County. This is elevation-tiered rather than a flat countywide requirement -- required for construction sites above 6,500 feet elevation, not required below it.
Logan County Planning and Zoning Department (Logan County, Colorado (unincorporated))
The county's "Logan County Roofing Requirements" page states: "Ice barrier is required for asphalt shingles, metal roof shingles, mineral roll roofing, slate, wood shingles, and wood shakes per R905.2.7.1, R905.3.1, R905.4.3.1, R905.6.3.1, R905.7.3.1, R905.8.3.1. Concrete and clay tile per R905.3.4 and R905.3.5 or manufacturer's instructions."
Montrose County Planning and Development - Building Division (Montrose County, Colorado)
Required. Montrose County's building code resolution sets its own climate and geographic design requirements table, and that table answers "Ice Barrier Underlayment Required" affirmatively for the unincorporated county.
Ouray County Land Use Department - Building (Ouray County, Colorado)
Ouray County Resolution No. 2021-049, Exhibit A, item 11, amends Table R301.2(1) to state "Ice Shield: Yes," a county-completed answer to the base 2018 IRC's Section R905.1.2 conditional ice- barrier trigger for areas with a history of ice forming along the eaves.
Pikes Peak Regional Building Department (El Paso County region, Colorado (including Colorado Springs and surrounding municipalities))
Conditional on elevation, not universal: "Properties that are above 7,000 ft. elevation require an ice barrier to be installed. This barrier shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering, polymer-modified bitumen sheet, and shall extend from the eave's edge to a point of at least 24 inches inside the exterior wall line of the building." Elevation is listed on the permit receipt. (See 2023 PPRBC section RBC303.4.2 Table R301.2 footnote D and 2021 IRC section 905.1.2 for application) Below 7,000 ft, no ice barrier is called out for typical reroofs in this handout.
Pitkin County Building Department (Pitkin County, Colorado (unincorporated))
Pitkin County Code Section 11.20.040's amended Table R301.2 lists "Ice Barrier Underlayment Required = YES 905.1.2" as the county-wide determination. The same section separately amends R905.1.2 Ice Barrier as operative text: "An ice dam barrier that consists of at least two layers of underlayment cemented together or of a self-adhering polymer modified bitumen sheet shall be used in lieu of normal underlayment and shall extend from the roof eave edge at least four and one-half feet inside the exterior wall line as measured along the roof surface, twenty-four inches from the centerline of the valley and up twenty-four inches on the vertical wall at a roof and wall juncture."
Rio Blanco County Building Division (Rio Blanco County, Colorado)
The County's Building Codes & Design Criteria page states plainly, among its printed design criteria: "Ice barrier underlayment required."
Rio Grande County Department of Building Safety (Rio Grande County, Colorado)
Rio Grande County's Table R301.2(1) design-criteria exhibit (linked from the Building Department's own "Rio Grande County Design Criteria IRC" document) prints "Ice Barrier Underlayment Required" as "YES."
Routt County Regional Building Department (Routt County, Colorado)
Routt County Un-Incorporated 2021 ICC Building Code Adoption resolution, Table R301.2(1) as amended: "Ice Shield Underlayment Required – Yes per IRC Section R905.1.2 Ice Barriers." Applies to unincorporated Routt County.
San Miguel County Building Department (San Miguel County, Colorado)
San Miguel County's amended IRC Table R301.2(1) (in the same "Amendments to the 2018 International Codes" document) prints an "ICE BARRIER UNDERLAYMENT REQUIRED" column with the value "YES" alongside the county's other climatic design figures. This is separate from the county's Section R328 "Wildfire Resistant Construction" amendment, which requires ignition- resistant roof-covering materials (tested to ASTM E108 or UL 790) -- a fire-class requirement, not an impact-resistance or ice-barrier one, and not used to support this field.
Summit County Building Inspection Department (Summit County, Colorado (unincorporated))
Table R301.2, as amended, prints "Ice Barrier Underlayment Required" as "yes" (footnote h: "In accordance with R905.1 as amended"). Resolution No. 2026-45, Exhibit A amends R905.1.2 Ice Barriers: "An ice dam protection underlayment that consists of an approved self-adhering polymer modified bitumen sheet shall be used with all roof coverings. This ice dam protection underlayment shall extend up the slope of the roof from the drip-edge of the roof or eave and cover the entire roof decking surface."
Teller County Building Division (Teller County, Colorado)
Teller County Building Code, Table R301.2(1) item 8 states: "ICE BARRIER UNDERLAYMENT REQUIRED: An ice barrier is required in Teller County for heated structures and shall be installed per Sections: R905.1.2, R905.2.7.1, R9054.3.1, R905.5.3.1, R905.6.3.1, R905.7.3.1 and R905.8.3.1." The amended Section R905.1.2 states: "In all habitable and/or conditioned structures where there is a potential for ice forming along the eaves causing a backup of water as designated in Table R301.2(1), an ice barrier that consists of at least two layers of underlayment cemented together or of a self-adhering polymer modified bitumen sheet, shall be used in lieu of normal underlayment and extend from the lowest edge of all roof surfaces to a point at least seventy-two (72) inches past the inside of the exterior wall line of the building. All valleys shall be lined with the same ice barrier centered at eighteen inches (18) out from either side of the valley. The addition of electrical service to a detached accessory structure shall not trigger this requirement."
Town of Alma - Building Department (Town of Alma, Colorado)
Alma Municipal Code § 18-1-20(22) (Ord. No. 2025-03, § 1, 6-17-2025) amends IRC Section R905.1.2 to read in its entirety: "R905.1.2 Ice Barriers. An ice dam protection that consists of an approved self-adhering modified bitumen sheet underlayment shall be used at all sloped roofs. This ice dam protection underlayment shall extend up the slope of the roof from the drip edge of the roof or eave and cover the entire roof deck surface. In new construction, ice dam protection shall extend a minimum 30 inches up walls adjacent to the roof surface. Exception: Detached accessory structures that do not contain conditioned space." The same section's Table R301.2(1) separately prints "Ice Barrier Underlayment Required" as "YES," consistent with this text.
Town of Arriba - Building Codes (Town of Arriba, Colorado)
Ordinance No. 154 replaces Section R905.1.2, Ice barriers, with its own provision, conditioned on roof slope rather than the base code's ice-forming-history designation: "On roofs with a slope equal to or less than four units vertical in 12 units horizontal (33-percent slope), an ice barrier shall be installed for asphalt shingles, metal roof shingles, mineral-surfaced roll roofing, slate and slate-type shingles, wood shingles and wood shakes," consisting of "not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet," extending from the lowest roof edges to a point not less than 24 inches inside the exterior wall line. The Town's amended Table R301.2 cross-refers to this section rather than stating a flat yes or no.
Town of Avon - Community Development Department (Building Division) (Town of Avon, Colorado)
Town of Avon Municipal Code Sec. 15.10.100, the amended Table R301.2, lists "Ice Barrier Underlayment Required = YES, 100%" as the townwide determination.
Town of Basalt Building Department (Town of Basalt, Colorado)
Basalt's amended Table R301.2(1) (Municipal Code § 18-22, item (7)) prints "Ice Barrier Underlayment Required: Yes."
Town of Bayfield - Building Division (Town of Bayfield, Colorado)
Bayfield Municipal Code § 4-89(4)'s Table R301.2(1) amendment prints "Yes" in the "Ice Shield Underlayment Required" column.
Town of Bennett Building Department (Town of Bennett, Colorado)
Required town-wide, and set by the Town rather than left to the model-code trigger. Bennett Municipal Code Section 18-7-20(10), enacted by Ordinance No. 806-25 on November 4, 2025, completes Table R301.2(1) of the adopted 2024 International Residential Code with the Town's own climatic and geographic design criteria, and the table's Ice Barrier Underlayment Required entry reads YES, with no qualifying footnote or elevation condition. The same table sets a 30 pound ground snow load, a 115 mph wind speed, Seismic Design Category B, severe weathering, a 36 inch frost line depth and a 1 degree Fahrenheit winter design temperature.
Town of Berthoud - Planning and Building Department (Town of Berthoud, Colorado)
"Ice Barrier IS REQUIRED per section R905.1.2" — the Design Criteria table in the same document also lists "Ice Barrier Underlayment Required: Yes."
Town of Blue River - Building Department (Town of Blue River, Colorado)
Blue River's amended Table R301.2(1) (Ordinance No. 2026-01, Sec. 18-2-40 item (12)) prints "Ice Barrier Underlayment Required: YES." The same ordinance separately deletes and rewrites IRC Section R905.1.2, Ice Barriers (Sec. 18-2-40 item (21)): "An ice dam protection that consists of an approved self-adhering modified bitumen sheet underlayment shall be used at all sloped roofs. This ice dam protection underlayment shall extend up the slope of the roof from the drip edge of the roof or eave and cover the entire roof deck surface. In new construction, ice dam protection shall extend a minimum 30 inches up walls adjacent to the roof surface." A parallel IBC Section 1507.1.2 amendment (Sec. 18-2-30 item (11)) adds the same requirement for the Building Code, with an exception for "Detached accessory structures not containing conditioned space."
Town of Bow Mar Building Department (Town of Bow Mar, Colorado)
Table R301.2(1) as amended by § 18-9(b)(1) prints "Ice shield underlayment Requires Yes (See R 905.1.2 Ice Barriers)."
Town of Breckenridge Building Division - Community Development (Town of Breckenridge, Colorado)
Table R301.2(1) as amended by § 8-1-5(A)(21) prints "Ice Barrier Underlayment Required" as "yes" (footnote i: "In accordance with R905.1.1 as amended"). § 8-1-5(A)(40) amends R905.1.2, Ice barriers, to read: "An ice dam protection that consists of an approved self-adhering modified bitumen sheet underlayment, or other similar material that meets the intent and is first approved by the building official, shall be used at all sloped roofs. This ice dam protection underlayment shall extend up the slope of the roof from the drip-edge of the roof or eave and cover the entire roof deck surface. In new construction ice dam protection shall extend a minimum 30 inches up walls and adjacent to the roof surface."
Town of Calhan - Building Code & Permits (Town of Calhan, Colorado)
Calhan's amended Table R301.2(1) (Municipal Code § 6.11.040(F)) prints "Ice Barrier Under-Layment Required: YES."
Town of Carbondale - Building Department (Town of Carbondale, Colorado)
Town of Carbondale Municipal Code Sec. 18-3-20 item (7), amended Table R301.2, lists "Ice Barrier Underlayment Required = Yes" as the townwide determination.
Town of Castle Rock - Building Division (Town of Castle Rock, Colorado)
Per CRMC 15.06.030 (Section R905.1.2, Ice barriers, as amended by Ordinance No. 2026-017, adopted 6/2/2026, effective 6/30/2026): an ice barrier shall be installed on eaves and valleys for asphalt shingles, metal roof shingles, mineral-surfaced roll roofing, slate and slate-type shingles, wood shingles, and wood shakes, consisting of not less than two layers of cemented underlayment or a self-adhering polymer-modified bitumen sheet, extending not less than 24 inches inside the exterior wall line. On roofs with slope 8:12 or greater, the ice barrier must also extend not less than 36 inches up-slope from the eave edge. Exception: detached accessory structures without conditioned floor area.
Town of Cedaredge - Planning & Building Department (Town of Cedaredge, Colorado)
Cedaredge Municipal Code § 15.05.040 ("Manual J design criteria Table R301.2(1) jurisdiction completion") prints the labeled line "Ice Barrier Underlayment: Yes." The companion Table R301.2(1) at § 15.05.030 prints the same field's cell as "Tributary Area Valleys Start Shingles" rather than a Yes/No value -- an apparent drafting artifact in that table -- so this field is sourced to the unambiguous § 15.05.040 statement rather than the garbled table cell.
Town of Columbine Valley Building Department (Town of Columbine Valley, Colorado)
§ 15.08.020(b)(3)'s design-criteria fill-in prints "Ice shield underlayment requires Yes (see Sec. 1507.2.8.2)." This corroborates the Town's own building-codes webpage, which independently states: "Ice barrier shall be used on the eave edge for all new roof tear-offs. The ice barrier shall extend 24 inches from the exterior wall."
Town of Crested Butte Building Department (Town of Crested Butte, Colorado)
Required town-wide. The Town of Crested Butte adds its own climatic and geographic design criteria table, and that table answers "Roof Ice Barrier Underlayment Required" with "Yes", so the ice barrier provisions of the adopted residential code apply to every roof in town.
Town of Dinosaur - Building Permits (Town of Dinosaur, Colorado)
Dinosaur Municipal Code § 12.14.020(VIII)(A)'s filled-in Table R-301.2(1) prints "Ice barrier underlayment required: Yes" as one of the added rows alongside the Town's other climatic design values.
Town of Eagle Building Department (Town of Eagle, Colorado)
The Town of Eagle's Table R301.2(1) amendment (2021 IRC Amendments) prints "Ice Barrier Underlayment: Yes" as one of the filled-in table values, confirmed by reading the rendered table image directly.
Town of Eaton - Building & Permitting (Town of Eaton, Colorado)
IRC Table R301.2(1) as filled in by item (14) of Eaton Municipal Code § 6-1-2 (Amendments to the International Residential Code): "ICE BARRIER UNDERLAYMENT REQUIRED YES".
Town of Fairplay - Building Department (Town of Fairplay, Colorado)
Fairplay Municipal Code § 18-1-20(c) item (9), Table R301.2(1) as filled: "Ice Barrier Underlayment Required: Yes." Item (13) separately rewrites R905.1.2 in full: "An ice dam protection that consists of an approved self-adhering modified bitumen sheet underlayment shall be used at all sloped roofs. This ice dam protection underlayment shall extend up the slope of the roof from the drip edge of the roof or eave and cover the entire roof deck surface. In new construction, ice dam protection shall extend a minimum 30 inches up walls adjacent to the roof surface" -- a universal, non-history-conditional mandate corroborating the table.
Town of Firestone - Building Division (Town of Firestone, Colorado)
R905.1.2. "Ice barriers are REQUIRED. The ice barrier shall extend from the lowest edges of all roof surfaces to a point not less than 24 inches (610 mm) inside the exterior wall line of the building." Mid- roof checklist adds: "Ice & Water installed over the drip on the eaves and underlayment under the drip edge on rakes."
Town of Fraser Building Department (Town of Fraser, Colorado)
Fraser Municipal Code § 18-1-40 item (56) deletes and rewrites R905.1.2: "An ice barrier that consists of an approved self-adhering polymer modified bitumen sheet shall be used in lieu of normal underlayment on all sloped roofs. Roof(s) under 4:12 pitch shall have double underlayment... This ice dam protection underlayment shall be installed from the eaves to a point 6 feet inside the exterior wall line of the building and 24 inches from the center line of all valleys, fully adhered to the substrate on all habitable structures. Exception: Detached accessory structures that contain no conditioned floor area." Item (57) additionally repeals "Sections R905.2.7.1, R905.4.3.1, R905.5.3.1, R905.6.3.1, R905.7.3.1 and R905.8.3.1... in their entirety" -- the base-IRC material-specific "history of local ice damming" trigger clauses -- so the ice-barrier mandate applies universally rather than case-by-case. (Fraser's own Table R301.2(1), item (31), omits the standard "Ice Barrier Underlayment Required" table row entirely; this field is sourced from the operative statute text instead.)
Town of Frederick - Building Department (Town of Frederick, Colorado)
Re-roof guidelines: "Ice and water barrier shall be installed on all roofs." The Design Criteria table on the same page separately lists "Ice barrier requirement - Yes." Mid-Roof Inspection checklist confirms: "All ice and water shield shall be in place."
Town of Frisco - Community Development Department (Town of Frisco, Colorado)
"Ice Barrier Underlayment Required: Yes" (IRC Table R301.2(1) as amended by § 65-3 item (7)), footnote h: "There has been a history of local damage from the effects of ice damming." Corroborated by § 65-3 item (27), which replaces R905.1.2 in its entirety to require an ASTM D1970 self-adhering ice dam protection underlayment on all roof coverings (R905.2 through R905.8, and R905.10), extending up the slope of the roof from the eave a minimum of 8 feet 6 inches inside the exterior wall line (exception: unconditioned detached accessory structures).
Town of Garden City - Building Permits (Town of Garden City, Colorado)
Garden City Municipal Code § 18-2-30(14)'s fill-in of IRC Table R301.2(1) prints "YES" in the "Ice Barrier Under-layment Required" column.
Town of Georgetown Building Department (Town of Georgetown, Colorado)
Required town-wide, with no elevation or roof-slope condition attached. The completed design criteria table in Georgetown Municipal Code Title 15 answers "Ice Shield Underlayment Required" with "YES", so the ice barrier provisions of the adopted International Residential Code apply to every roof in town.
Town of Gilcrest Planning & Zoning Department (Town of Gilcrest, Colorado)
Gilcrest Municipal Code § 18-24(l)'s Table R301.2(1) amendment prints "YES" in the "Ice barrier Underlayment Required" column.
Town of Granby - Building Department (Town of Granby, Colorado)
The town's 2021 IRC amendment ordinance (Chapter 15.05.050, read in full) adds Section R905.1.1 Ice Barrier: an approved self-adhering polymer-modified bitumen ice barrier is required in lieu of normal underlayment on all sloped roofs of habitable structures, installed from the eaves to a point 6 feet inside the exterior wall line and 24 inches from the center line of all valleys, fully adhered to the substrate. Detached accessory structures with no conditioned floor area are exempted.
Town of Grand Lake - Building Permits (Grand County Building Department) (Town of Grand Lake, Colorado)
Grand County's 2015 local amendments, adopted by the Town at Municipal Code Sec. 9-1-2(B), add Section R905.1.2: "An ice barrier that consists of an approved self-adhering polymer modified bitumen sheet shall be used in lieu of normal underlayment on all sloped roofs. This ice dam protection underlayment shall be installed from the eaves to a point 6 feet inside the exterior wall line of the building and 24 inches from the center line of all valleys, fully adhered to the substrate on all habitable structures." The only exception is for detached accessory structures containing no conditioned floor area. The County's completed Table R301.2(1) also states "ICE BARRIER - YES". This requirement is stable across the County's edition change: the corresponding provision in its 2021 amendment package is materially identical.
Town of Green Mountain Falls (Pikes Peak Regional Building Department) (Town of Green Mountain Falls, Colorado)
Conditional on elevation, not universal: Section RBC303.4.2 of the 2017 Pikes Peak Regional Building Code (as amended effective December 7, 2018 -- the edition and printing the Town's own Municipal Code Sec. 18-1 adopts by reference) prints "Ice Barrier Underlayment Required ... YES" in Table R301.2(1), with a footnote: "Required only for buildings and structures with a grade plane at or above 7,000 ft (2,134 m) elevation." The Town straddles El Paso and Teller Counties; elevation determines applicability per the printed footnote, not a townwide flat rule.
Town of Gypsum Building Department (Town of Gypsum, Colorado)
Town of Gypsum Municipal Code Sec. 15.01.040's printed climatic and geographic design criteria table lists "ICE BARRIER AIR UNDERLAYMENT = Yes" as the townwide determination.
Town of Haxtun Building Department (Town of Haxtun, Colorado)
Haxtun Municipal Code section 150.02(B)(8), completing IRC Table R301.2(1) for the Town, states "ICE BARRIER UNDERLAYMENT REQUIRED: YES." Adopted by Ordinance 2025-1, passed October 6, 2025, as part of the Town's 2018 International Residential Code adoption.
Town of Hayden (permits via Routt County Regional Building Department) (Town of Hayden, Colorado)
Town of Hayden 2021 ICC Building Code Adoption resolution, Table R301.2(1) as amended: "Ice Shield Underlayment Required – Yes per IRC Section R905.1.2 Ice Barriers."
Town of Hot Sulphur Springs (Grand County Building Department) (Town of Hot Sulphur Springs, Colorado)
Grand County's building code, adopted by the Town by reference (Resolution 2018-5-31 / Ordinance No. 21, Exhibit A, amending the 2015 International Residential Code), amends Section R905.1.2: "An ice barrier that consists of an approved self-adhering polymer modified bitumen sheet shall be used in lieu of normal underlayment on all sloped roofs. This ice dam protection underlayment shall be installed from the eaves to a point 6 feet inside the exterior wall line of the building and 24 inches from the center line of all valleys, fully adhered to the substrate on all habitable structures." The only exception is for detached accessory structures with no conditioned floor area.
Town of Hotchkiss - Building Permits/Inspections (Town of Hotchkiss, Colorado)
The Town's "Getting Started... A Guide for the Building Process" handout lists among its building requirement reminders: "Ice and water shield is required as a first course as well as in valleys."
Town of Hudson - Building Department (Town of Hudson, Colorado)
The Town's 2021-22 Roofing Regulations handout's Table R301.2(1) lists "Ice Barrier Underlayment Required Yes"; footnote: "*Ice Barrier IS REQUIRED per section R905.1.2."
Town of Ignacio Planning Department (Building Permits) (Town of Ignacio, Colorado)
The Town's own Table 301.2(1), Climatic and Geographic Design Criteria, added by Ordinance 357 Section 5-6(4), sets "Ice Shield Underlayment Required: Yes" for Ignacio. Under the unamended 2018 IRC Section R905.1.2 that this table triggers, "In areas where there has been a history of ice forming along the eaves causing a backup of water as designated in Table R301.2(1), an ice barrier shall be installed," consisting of not fewer than two layers of underlayment cemented together, or a self-adhering polymer- modified bitumen sheet, extending from the lowest roof edges to a point not less than 24 inches inside the exterior wall line, for asphalt shingles, metal roof shingles, mineral-surfaced roll roofing, slate and slate-type shingles, wood shingles and wood shakes.
Town of Johnstown - Building Department (Town of Johnstown, Colorado)
Ice Barrier Requirements: required from the lowest edges of all roof surfaces to a point at least 24 inches inside the exterior wall line.
Town of Keenesburg Building Department (Town of Keenesburg, Colorado)
Keenesburg Municipal Code § 18-1-20(c)(10)'s Table R301.2(1) amendment prints "Ice Barrier Underlayment Required: Yes" as a filled-in row. The Town's separately published Re-Roof requirements sheet confirms in plain language: "Ice Barrier is required. The ice barrier shall extend from the lowest edges of all roof surfaces to a point not less than 24 inches inside the exterior wall line of the building."
Town of Kremmling Building Permits (Town of Kremmling, Colorado)
Required. Kremmling adopts Grand County's building code by reference, and both of the county amendment sets in the adoption chain require an ice barrier: the county's completed climatic and geographic design criteria table answers the ice barrier row affirmatively, and the county's roof-covering amendments carry ice barrier cross-references for asphalt shingles, metal shingles, mineral-surfaced roll roofing, slate, wood shingles and wood shakes alike.
Town of Lake City - Building Permits (Hinsdale County Building Department) (Town of Lake City, Colorado)
The 2015 IRC conditions the ice barrier on a local designation: Section R905.1.2 requires one "In areas where there has been a history of ice forming along the eaves causing a backup of water as designated in Table R301.2(1)," consisting of "not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet ... extend[ing] from the lowest edges of all roof surfaces to a point not less than 24 inches inside the exterior wall line of the building," with 36 inches measured along the slope where the roof pitch is 8:12 or greater, and an exception for detached accessory structures not containing conditioned floor area. Hinsdale County, which administers building permits for the Town, makes that designation in its published "Building Planning/Design Criteria (From IRC Table R301.2(1))," which states "Ice Barrier Underlayment: To 24" inside exterior wall." An ice barrier is therefore required here.
Town of LaSalle - Building Department (Town of LaSalle, Colorado)
LaSalle Municipal Code Sec. 18-147(16)'s Table R301.2(1) amendment prints "Ice Barrier Underlayment Required" as "Yes" alongside the town's other climatic design values.
Town of Limon Building Department (Town of Limon, Colorado)
The Town's "Basic Construction Requirements" handout prints: "Ice Barrier on 4/12 or Less from Eves 24" Inside Extension Walls" - i.e. ice barrier underlayment is required on roof slopes of 4:12 or less, extending 24 inches inside the exterior wall line.
Town of Lochbuie - Building Department (permits via SAFEbuilt) (Town of Lochbuie, Colorado)
Required town-wide, with no elevation or roof-slope condition attached. The Town of Lochbuie completed International Residential Code Table R301.2(1) at Municipal Code Section 18-1-20(d), and the table answers "Ice Barrier Underlayment Required" with "YES". The ice barrier provisions of the adopted 2024 International Residential Code therefore apply to every roof in town.
Town of Meeker - Community Development Department (Town of Meeker, Colorado)
The Town of Meeker's local amendment to the 2003 International Residential Code Table R301.2(1), Section 15.5.102, sets "Ice Shield Underlayment Required" to "Yes," alongside a 40 psf ground snow load and an 80 mph wind speed.
Town of Milliken (permits via SAFEbuilt) (Town of Milliken, Colorado)
Required town-wide, with no elevation or roof-slope condition attached. Milliken Municipal Code Section 18-10-20 completes IRC Table R301.2(1) for the Town, and the completed table answers "Ice Barrier Underlayment Required" with "Yes". The ice barrier provisions of the adopted 2024 International Residential Code therefore apply to every roof in town.
Town of Monument (permits via Pikes Peak Regional Building Department) (Town of Monument, Colorado)
PPRBD reroof guidelines: "Elevations of the property is listed on the permit receipt. Properties that are above 7,000 ft. elevation require an ice barrier to be installed. This barrier shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering, polymer-modified bitumen sheet, and shall extend from the eave's edge to a point of at least 24 inches inside the exterior wall line of the building." Confirmed by PPRBD homeowner FAQ: "If the elevation on the property is more than 7,000 feet, ice and water shield is required. If it is below 7,000 feet in elevation, it is not required." Trigger is per-property elevation (shown on the permit receipt), not a town-wide rule.
Town of Morrison Building Department (Town of Morrison, Colorado)
Required town-wide. The Town of Morrison completes the climatic and geographic design criteria table, and that table answers "Ice Shield Underlayment Required" affirmatively, so the ice barrier provisions of the adopted residential code apply to every roof in town.
Town of Mt. Crested Butte Building Division (Town of Mt. Crested Butte, Colorado)
Town of Mt. Crested Butte Ordinance No. 6, Series 2024, Sec. 6-65 amends International Residential Code Section R905.1.2 in its entirety: "Section R905.1.2, Ice Barriers. An ice barrier shall be installed for all roofs. The ice barrier shall consist of a self-adhering polymer-modified bitumen sheet and shall be installed on the entire roof. Exception: Detached accessory structures not containing conditioned floor area." (A parallel IBC-track amendment appears at Sec. 6-31, amending Section 1507.2.8.2, with identical operative text.) This is a local ice-barrier-underlayment mandate under the IRC roof-covering chapter and is distinct from the separately-adopted Colorado Wildfire Resiliency Code's Class A roof-covering (ignition-resistance) requirement, which this record does not use to support impact-resistance or ice-barrier fields.
Town of Nederland Building, Planning & Zoning Department (Town of Nederland, Colorado)
Table R301.2(1) as amended by § 18-2 (embedded table image "8-2.png") prints "Ice Barrier Underlayment Required" as "Yes." No accompanying footnote-definition legend is printed in the codified text beneath the table.
Town of New Castle - Building Department (Town of New Castle, Colorado)
Town of New Castle Municipal Code Sec. 15.10.020's amended Table R301.2 lists "Ice Shield Underlayment Required = Yes" as the townwide determination.
Town of Oak Creek (Routt County Regional Building Department) (Town of Oak Creek, Colorado)
Required. The Town of Oak Creek amends the climatic and geographic design criteria table and answers "Ice Shield Underlayment Required" with "Yes per IRC Section R905.1.2 Ice Barriers", so the ice barrier provisions of the adopted residential code apply to every roof in town.
Town of Ophir - Building Department (Town of Ophir, Colorado)
Table R301.2(1) as amended by Ophir Land Use Code Appendix B (2018 IRC Amendments) prints "Ice Barrier Underlayment Required" as "YES" in its single unbanded design-criteria row.
Town of Orchard City - Building Department (Town of Orchard City, Colorado)
Orchard City's local amendment to the 2018 International Residential Code Table R301.2(1), Climatic and Geographic Design Criteria, sets 'Ice Barrier Underlayment' to 'Yes,' alongside a 30 psf ground snow load and a 115 mph (Ultimate, Exposure C) wind speed.
Town of Pagosa Springs Building Division (Town of Pagosa Springs, Colorado)
Ordinance No. 1034, Series 2026, § 6.13.5, completes IRC Table R301.2(1) (Climatic and Geographic Design Criteria) as adopted with the 2024 IRC: "Ice Shield Underlayment Required: Yes, at permitters per code." The ordinance's own wording is unusual ("permitters" rather than the likely intended "perimeters") but the requirement itself is stated as an unqualified "Yes." Wind speed and ground snow load in the same table are determined per- parcel via the ASCE 7 Hazard Tool rather than a fixed town-wide figure.
Town of Palmer Lake (permits via Pikes Peak Regional Building Department) (Town of Palmer Lake, Colorado)
Required by elevation rather than town-wide. Table R301.2 of the Pikes Peak Regional Building Code lists ice barrier underlayment as required, qualified by footnote d, which limits it to "buildings and structures with a grade plane at or above 7,000 ft (2,134 m) elevation." The trigger is the elevation of the individual property, which the Pikes Peak Regional Building Department prints on the permit receipt. Where it applies, the department's reroof guidance describes the barrier as "not fewer than two layers of underlayment cemented together, or a self-adhering, polymer-modified bitumen sheet," extending from the eave's edge to a point at least 24 inches inside the exterior wall line of the building.
Town of Parachute - Building & Permitting (Town of Parachute, Colorado)
The Town's completed IRC Table R301.2(1) (Ordinance No. 793-2021, Exhibit A, Chapter 13.60.020, item T) states "Ice Shield Underlayment Required: Yes," so an ice-barrier membrane is required under the Town's adopted Residential Code.
Town of Pierce Building Permit Department (Town of Pierce, Colorado)
Pierce Municipal Code § 18-2-30(14)'s Table R301.2(1) amendment prints "Ice Barrier Underlayment Required: YES." The Town's Design Criteria webpage independently confirms, under Special Construction Requirements: "Ice and water shield required."
Town of Platteville - Building Department (SAFEbuilt) (Town of Platteville, Colorado)
IRC Table R301.2(1) as filled in by Platteville Code of Ordinances § 18-10-30 lists "Ice Barrier Underlayment Required Yes". Corroborated by the town's own SAFEbuilt Residential Asphalt Shingle Re-Roofing Requirements handout: "Ice and water shield IS REQUIRED from the eves to 24" inside the warm wall."
Town of Ridgway - Building Department (Town of Ridgway, Colorado)
Ridgway Municipal Code § 6-1-3(A)(12)'s Table R301.2(1) amendment prints "Ice Barrier Underlayment Required: Yes" as an added row alongside the town's other climatic design values.
Town of Severance Building Department (Town of Severance, Colorado)
IRC Table R301.2(1) as filled in by Severance Municipal Code § 18-2-30 lists "Ice Barrier Underlayment Required YES". Corroborated by the Town's 2024-IRC Residential Re-Roof Guide (SAFEbuilt, 1.1.2026): "ICE AND WATER SHIELD IS REQUIRED ON ALL ROOFS."
Town of Silt - Community Development Department (Town of Silt, Colorado)
Required town-wide, with no elevation or roof-slope condition attached. The Town of Silt completes International Residential Code Table R301.2(1) in its local amendment list, and the completed table answers "Ice Barrier Underlayment Required" with "Yes". The table footnote carried with it explains the basis: an ice barrier is called for "for areas where the average daily temperature in January is 25F (-4C) or less, or where there has been a history of local damage from the effects of ice damming." The ice barrier provisions of the adopted residential code therefore apply to every roof in town.
Town of Silver Plume - Building Permits (Town of Silver Plume, Colorado)
Required town-wide. The Town of Silver Plume completes International Residential Code Table R301.2(1) at Section 5(G) of Ordinance No. 345, and the completed table answers "Ice Shield Underlayment Required" with "YES". The Town also inspects for it specifically: its roofing inspection list requires a "Mid-roof inspection of ice and snow shield required 4 feet up from exterior walls."
Town of Silverthorne - Community Development Department (Building Division) (Town of Silverthorne, Colorado)
Required over the ENTIRE roof deck, not just at the eaves -- a materially stricter rule than the model code. The Town of Silverthorne amends International Residential Code Section R905.1.2 to read: "An ice dam protection underlayment that consists of an approved self-adhering polymer modified bitumen sheet shall be used with all roof coverings. This ice dam protection underlayment shall extend up the slope of the roof from the drip-edge of the roof or eave and cover the entire roof decking surface." The completed Table R301.2(1) separately answers "Ice Barrier Underlayment Required" with "Yes".
Town of Snowmass Village - Building Division (Town of Snowmass Village, Colorado)
Town of Snowmass Village Municipal Code Sec. 18-242(a), amended IRC Table R301.2(1), lists "Ice Barrier = Yes" as the townwide determination.
Town of Superior - Planning and Building Department (Town of Superior, Colorado)
"Ice and water shield is required on all eaves. A minimum of one 3' wide strip of ice and water shield is required." For low-slope roofs (2:12 to 4:12 pitch): "apply a double layer of underlayment felt per section R905.2.3 IRC or apply a single layer of ice barrier on entire slope and 24" on adjacent slope."
Town of Telluride Building Department (Town of Telluride, Colorado)
The Town's own amended Table R301.2 (Climatic and Geographic Design Criteria, 2024 IRC as adopted by Ordinance 1620, Sec. 15-2-30 item 4) lists "Ice barrier underlayment required: Yes" among the design criteria set for the Town of Telluride. This is a locally-set table entry in the Town's own adopted code, not merely a default inherited from the base model code.
Town of Wellington - Building and Planning Department (Town of Wellington, Colorado)
IRC Table R301.2 as filled in by Wellington Municipal Code § 18-2-30 lists "ICE BARRIER UNDERLAYMENT REQUIRED Yes". Corroborated by the town's older 2021 Roofing Regulations handout: "*Ice Barrier is required per section R905.1.2."
Town of Wiggins Building Department (Town of Wiggins, Colorado)
The Town's own "ROOF REGULATIONS" sheet (Building Department) states: "Ice Barrier IS REQUIRED per section R905.1.2," referencing the 2018 International Residential Code the Town has adopted; the same document's climatic and geographic design-criteria table separately lists "Ice Barrier Underlayment Required" as "Yes."
Town of Windsor - Building Department (Town of Windsor, Colorado)
"ICE AND WATER SHIELD IS REQUIRED ON ALL ROOFS" (2024 IRC Residential Re-roofing guide, Town of Windsor / SAFEbuilt, published 1.1.2026); corroborated by the Town's separate Design Criteria sheet, which lists under Special Requirements: "Ice and water shield required".
Town of Winter Park Building Division (Town of Winter Park, Colorado)
Required, and the Town states the requirement directly in its own amendments rather than through a table cell. Winter Park sits at roughly 9,000 feet and its amended ice barrier provision governs, alongside a separate local requirement that valley lining be fully adhered to the substrate for twenty-four inches from the valley centre line on all habitable structures, with an exception only for detached accessory structures containing no conditioned floor area.
Town of Yampa - Building Department (Town of Yampa, Colorado)
The Town of Yampa's own completion of IRC Table R301.2(1), Climatic and Geographic Design Criteria, in Title 15 of its Municipal Code, states "Ice Shield Underlayment Required -- Yes." The same table also sets a 90 mph design wind speed and Seismic Design Category B.
Ice barrier required — Indiana (1)
Ice barrier required — Iowa (15)
City of Ames, Iowa - Inspections Division (City of Ames, Iowa)
Required under BOTH of the criteria sets Ames currently publishes, so this answer does not turn on the unsettled edition question. The codified set, Ames Municipal Code Sec. 5.201 amending IRC Table R301.2(1), states "Ice Shield Underlayment Required Yes"; the Inspections Division's "Local Design Criteria" table for the 2024 International Residential Code lists "Ice Shield Underlayment required: Yes" for the city.
City of Ankeny, Iowa - Development Services / Building Division (City of Ankeny, Iowa)
The City of Ankeny's own Table R301.2 insert (Municipal Code Sec. 184.20, applicable to the 2024 IRC as adopted at Chapter 184/Ordinance 2220) lists "Ice Barrier Underlayment Required: Yes." The city's Building Official's signed "Roof/re-roof compliance" letter separately cites IRC section "R905.2.7 Ice Barrier - required" as one of the code sections applicable to asphalt shingle roofing in Ankeny.
City of Cedar Rapids, Iowa - Building Services Department (City of Cedar Rapids, Iowa)
CITY-PUBLISHED requirement. The City of Cedar Rapids Building Services Department's roofing permit application / roofing standards require eave protection (ice dam protection) from the eave edge to a minimum of 24 inches inside the wall line - the standard IRC ice-barrier extent. The same city roofing standards specify 15-pound felt underlayment with laps of 2 inches for roof pitches of 4:12 and greater. Cedar Rapids is in a historically ice-dam-prone climate, and unlike Minnesota - where the ice barrier is imposed statewide by rule - this requirement here rests on Cedar Rapids' own adopted code and published roofing standards.
City of Davenport, Iowa - Building and Land Development (Building Division) (City of Davenport, Iowa)
CITY-SPECIFIC, sourced from Davenport's own local amendment table, not borrowed from any other jurisdiction. Davenport Municipal Code Sec. 15.12.052.A amends Table R301.2(1) of the adopted International Residential Code with Davenport-specific climatic and geographic design criteria, which include "Ice Barrier Underlayment Required" as "YES." See wind_design_criteria for the full table.
City of Des Moines, Iowa - Development Services Department, Permit and Development Center (City of Des Moines, Iowa)
Required both through the city's adopted code and through the city's own published guidance. The Table R301.2(1) climatic and geographic design criteria set out in Des Moines Municipal Code Sec. 26-300(g), as currently codified, list "Ice Shield Underlayment Required" as "Yes" for the city. The City of Des Moines Permit & Development Center handout "Residential Asphalt Shingle Requirements" separately spells out the ice-barrier specification for asphalt shingle roofs: an ice barrier of not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet used in place of normal underlayment, extending from the lowest roof edges to a point not less than 24 inches inside the exterior wall line, with an additional 36-inch extension measured along the slope on roofs of 8:12 pitch or greater; detached accessory structures without conditioned floor area are excepted. The handout's edition label predates the city's 2024 code update (see adopted_code), so the precise IRC section number for this provision was not re-confirmed against the 2024 edition, but the underlying requirement is independently corroborated by the current Table R301.2(1) codification.
City of Fort Dodge, Iowa - Building Safety (City of Fort Dodge, Webster County, Iowa)
Required. Municipal Code section 14.04.040 completes Table R301.2(1) for the city and states at item (4)(f) "Ice shield underlayment: Yes." That entry is what switches the requirement on rather than merely describing the weather: the adopted International Residential Code conditions its ice barrier provisions on a history of local damage from ice damming as designated in Table R301.2(1), and Fort Dodge has made the designation. Where the barrier is required the code calls for it to extend from the lowest edges of all roof surfaces to a point at least 24 inches inside the exterior wall line of the building.
City of Iowa City, Iowa - Building Inspection Services (City of Iowa City, Iowa)
Required, and confirmed against the CURRENT adopted edition rather than the superseded 2009 ordinance. Iowa City Code 17-1-1 adopts the 2024 IRC; 17-1-3 modifies IRC Table R301.2(1) with local data, and the "Ice barrier underlayment required" column for Iowa City reads "Yes." That entry is what activates the model code's ice barrier provision at IRC R905.1.2 for this jurisdiction. Iowa City does NOT amend that provision or any other section of IRC Chapter 9 (Roof Assemblies) - its 17-1-3 amendments reach 24 IRC sections and none of them is in Chapter 9 - so the trigger is local but the substantive ice barrier requirement is the unamended 2024 IRC text, which is behind the ICC paywall and is not restated here. The supporting climatic context from the same amended table: weathering Severe, frost line depth 42 inches, mean annual temperature 50 degrees F, air freezing index 2000, and an outdoor winter design dry-bulb temperature of -6 degrees F in the accompanying Manual J block - an ice-dam climate on its face.
City of Marion, Iowa - Building Services (City of Marion, Linn County, Iowa)
Required. Requirement 4 of the City of Marion asphalt shingle roofing handout, headed Ice Dam Protection, provides that "an ice barrier meeting ASTM D 1970 shall consist of a self-adhering polymer modified bitumen sheet (ice guard) or 2 layers of underlayment cemented together," and that "ice dam protection shall extend from the eaves edge to a point 24 inches inside the exterior wall line of the building." Two details in that wording are worth carrying to the job. The city accepts an alternative to a membrane - two layers of underlayment cemented together satisfy the requirement as written. And the ice barrier is the starting course for the underlayment schedule that follows it: on roofs of 2:12 up to 4:12 the handout directs "apply ice barrier as stated above," then a 19 inch strip of underlayment, then 36 inch wide sheets overlapping successive sheets 19 inches, while on roofs of 4:12 or greater the ice barrier is followed by a single layer of underlayment applied shingle fashion with a 2 inch overlap and end laps offset by 6 feet.
City of Mason City, Iowa - Building Inspections Division (City of Mason City, Cerro Gordo County, Iowa)
Required. Mason City completed Table R301.2 of the 2024 International Residential Code for the city and entered "YES" in the ICE BARRIER UNDERLAYMENT REQUIRED column. That entry is the operative act rather than a description of the weather: note h to the table directs a jurisdiction to fill the column in with "YES" where there has been a history of local damage from the effects of ice damming, and the roof covering sections of the adopted code condition their ice barrier requirements on that designation. Where the barrier is required the code calls for it to extend from the lowest edges of all roof surfaces to a point at least 24 inches inside the exterior wall line of the building.
City of Sioux City, Iowa - Permit Center (City of Sioux City, Iowa)
The City of Sioux City's own Table R301.2 insert at Sioux City Municipal Code Sec. 20.04.040, item 13 (applicable to the 2024 IRC as adopted at Sec. 20.04.030), lists "Ice Shield Required: Yes" as a filled-in table cell for the jurisdiction.
City of Urbandale, Iowa - Community Development Department (City of Urbandale, Polk and Dallas Counties, Iowa)
Required, and read the second half of this note before relying on an exception. Urbandale Municipal Code section 150.03(B)(14) fills in Table R301.2(1) with "ice shield underlayment required: YES," which is the designation that switches the adopted code ice barrier provisions on. THE CITY OWN FOOTNOTE TO THAT TABLE ENTRY PROMISES AN ALTERNATIVE THAT THE CODE DOES NOT CONTAIN. The asterisk on "YES" carries the note "See amendment to IBS section 1507.2.8.2 and IRC section R905.2.7.1 regarding ice shield alternative" - IBS being an evident slip for IBC. The whole of Municipal Code Chapter 150 was read, covering sections 150.01 through 150.99 and including the complete residential amendment list at 150.03, which runs to thirty-four numbered items, and the building code amendment list at 150.04. There is no amendment to IBC section 1507.2.8.2 and none to IRC section R905.2.7.1 anywhere in the chapter; the only occurrences of either section number in the whole of Chapter 150 are inside the footnote that promises them. So on the enacted text the ice barrier requirement stands without the alternative, and a roofer intending to use an alternative assembly should get the building official position in writing first rather than rely on a cross-reference that leads nowhere.
City of Waterloo, Iowa - Building Permitting & Inspections (City of Waterloo, Iowa)
The City of Waterloo's own Ice Barrier Requirement handout quotes 2021 IRC R905.2.7 and R905.1.2 verbatim and its own Table 301.2 insert lists "Ice Barrier Underlayment Required: yes." The handout describes the barrier as required for asphalt shingles, metal roof shingles, mineral-surfaced roll roofing, slate and slate-type shingles, wood shingles and wood shakes, extending from the lowest roof edges to at least 24 inches inside the exterior wall line (36 inches on slopes of 8:12 or greater).
City of West Des Moines, Iowa - Development Services Department, Building Inspection Division (City of West Des Moines, Iowa)
The City of West Des Moines's own "One and Two Family Residential Plan Submittal Requirements & General Code Review Conditions" checklist instructs applicants to "Install ice and water membrane per building code where required on shingle roof systems," and separately states that "eave overhangs use may be exempted if energy efficient trusses are used." The checklist does not cite a specific code section number or state the underlayment's required extension distance up the roof slope; those figures would be set by the city's own climatic and geographic design-criteria table, which was not located as an independently published document on the city's own site.
Linn County, Iowa - Building Permits & Inspections (Linn County, Iowa)
Linn County's own Table R301.2(1) insert at Code of Ordinances Sec. 105-17, item (11) (applicable to the 2024 IRC as adopted at Sec. 105-16), lists "Ice Barrier Underlayment Required: YES" as a filled-in table cell for the jurisdiction.
Polk County, Iowa - Public Works, Building Services (Polk County, Iowa)
Polk County's own Table R301.2(1) insert at Construction Code Sec. 20.2.4, item 18 (applicable to the 2021 IRC as adopted for unincorporated Polk County), lists "Ice Shield Under Layment Required: Yes" as a filled-in table cell for the jurisdiction. The same table appears verbatim on the Building Services webpage.
Ice barrier required — Kansas (7)
City of Leawood - Code Services / Building Permits (City of Leawood, Kansas)
The City's "Roofing Requirements" summary lists: "Ice Barrier Underlayment Required – at the lowest edges of all roof surfaces to a point at least 24 inches inside the exterior wall line of the building (sometimes 2 or 3 passes is required). Solid sheathing is required on that portion of the roof requiring the application of an ice barrier (wood shake and wood shingle roofs) – R905.2.7.1." The city's amended Table R301.2(1) sets "Ice Barrier Underlayment Required: Yes" city-wide, and the "Inspection Procedures" document confirms inspectors verify at the mid-phase roof inspection that "Ice and Water Shield is installed 24" inside the warm air wall at the eaves."
City of Lenexa - Building Codes Division (City of Lenexa, Kansas)
"Ice Barrier Underlayment (Section R905.1.2): Ice barrier shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet shall be used in place of normal underlayment and extend from the lowest edges of all roof surfaces to a point not less than 24 inches inside the exterior wall line of the building. On roofs with slope equal to or greater than eight units vertical in 12 units horizontal the ice barrier shall also be applied not less than 36 inches (914 mm) measured along the roof slope from the eave edge of the building. Note: Many manufacturers require ice barrier underlayment in valleys" (City of Lenexa, Residential Asphalt Roofing - Code Summary, rev. 11/2024).
City of Olathe - Building Codes Division (City of Olathe, Kansas)
"Ice Barrier Underlayment – The ice barrier shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet shall be used in place of normal underlayment and extend from the lowest edges of all roof surfaces to a point not less than 24 inches inside the exterior wall line of the building. On roofs with slope equal or greater than eight units vertical in 12 units horizontal (67 percent slope), the ice barrier shall also be applied not less than 36 inches measured along the roof slope from the eave edge of the building – IRC R905.1.2" (City of Olathe, Residential Building Permits page, "Roofing" section).
City of Overland Park - Building Safety Division (City of Overland Park, Kansas)
"An ice barrier is required. Ice barriers shall be installed for asphalt shingles, metal roof shingles, mineral-surfaced roll roofing, slate and slate-type shingles, wood shingles and wood shakes. The ice barrier shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet shall be used in place of normal underlayment and extend from the lowest edges of all roof surfaces to a point not less than 24 inches (610 mm) inside the exterior wall line of the building. On roofs with a slope equal to or greater than eight units vertical in 12 units horizontal (67 percent slope), the ice barrier shall also be applied not less than 36 inches (914 mm) measured along the roof slope from the eave edge of the building" (City of Overland Park, Residential Building Permit Exceptions and Guidance, "Ice Barriers" section).
Johnson County - Building Codes Division (Johnson County, Kansas (unincorporated))
Table R301.2(1) Climatic and Geographic Design Criteria, as amended by the Johnson County Code of Regulations for Buildings and Construction, 2018 Edition (Article 3, Section 5(d)), lists "Yes" in the Ice Barrier Underlayment Required column. The county's own "Requirements for Residential Roof Coverings" handout (effective July 1, 2020) reproduces the triggering condition at R905.1.2: "In areas where there has been a history of ice forming along the eaves causing a backup of water as designated in Table R301.2(1), an ice barrier shall be installed... and extend from the lowest edges of all roof surfaces to a point not less than 24 inches (610 mm) inside the exterior wall line of the building. On roofs with slope equal to or greater than eight units vertical in 12 units horizontal, the ice barrier shall also be applied not less than 36 inches (914 mm) measured along the roof slope from the eave edge."
Unified Government of Wyandotte County and Kansas City, Kansas - Building Inspection (City of Kansas City, Kansas)
The Unified Government of Wyandotte County/Kansas City, Kansas amends IRC Table R301.2(1) (Code Sec. 8-412, Article VII, One- and Two-Family Dwellings; Ord. No. O-97-22, 6-30-2022) to list "Ice Barrier Underlayment Required: Yes." Under the unamended 2018 IRC R905.1.2 baseline this extends from the eave edge to 24 in. inside the exterior wall line on all eaves. One consolidated code governs both the city and the county. Architect-verified directly on the current codification, 2026-07-18.
Unified Government of Wyandotte County and Kansas City, Kansas - Building Inspection (Wyandotte County, Kansas)
The Unified Government of Wyandotte County/Kansas City, Kansas amends IRC Table R301.2(1) (Code Sec. 8-412, Article VII, One- and Two-Family Dwellings; Ord. No. O-97-22, 6-30-2022) to list "Ice Barrier Underlayment Required: Yes." Under the unamended 2018 IRC R905.1.2 baseline this extends from the eave edge to 24 in. inside the exterior wall line on all eaves. One consolidated code governs both the city and the county. Architect-verified directly on the current codification, 2026-07-18.
Ice barrier required — Minnesota (24)
City of Apple Valley, Minnesota - Building Inspections (City of Apple Valley, Minnesota)
Apple Valley states the requirement in its own words on its Roofing page: "Ice protection shall be installed on all roofs, including porches and attached garages. Ice protection is not required on unheated detached accessory structures. Protection shall be from the eave to a point twenty-four (24) inches inside the exterior wall line. The ice barrier shall consist of two layers of felt cemented together or a self-adhering polymer modified bitumen sheet." Note the exemption turns on an accessory structure being both DETACHED and UNHEATED, not on detachment alone. The City adds a documentation requirement: "Photos of the ice barrier are required on site at the scheduled final inspection," and separately asks that those photos be emailed to [email protected] with the address or permit number in the subject line. This is state-governed content rather than a city choice: Minnesota Rules part 1309.0301, subpart 2 amends IRC Table R301.2(1) to read "ICE BARRIER UNDERLAYMENT REQUIRED[h] ... Yes" for the whole state. Apple Valley also requires underlayment beneath the shingles in addition to the ice barrier: "underlayment is required under all asphalt shingles and shall consist of a minimum of one layer of #15 felt or other approved products."
City of Blaine, Minnesota - Building Inspections Division (City of Blaine, Minnesota)
Blaine's own "Residential Roofing" reference handout states directly: "An ice and water barrier is required on all roofs, except for detached accessory buildings (garages). The barrier may consist of at least two layers of underlayment cemented together or a self-adhering polymer-modified bitumen sheet... The ice and water barrier must extend from the edge of the eaves to a point 24 inches inside the exterior wall line of the building. Ice and water barriers are required full-length in valleys." It further clarifies: "Ice and water protection is required on all attached garages. Exception: Detached accessory structures that contain no conditioned floor area," and "A maximum of two layers of ice and water barrier is permitted." This matches Minnesota Rules part 1309.0301, subpart 2, which amends IRC Table R301.2(1) to pre-fill "ICE BARRIER UNDERLAYMENT REQUIRED... Yes" statewide -- Blaine has no authority to opt out (Minn. Stat. § 326B.121, subd. 2(c)).
City of Bloomington, Minnesota - Building and Inspections Division (City of Bloomington, Minnesota)
STATE-GOVERNED, NOT CITY-SET -- applies identically in Bloomington as everywhere else in Minnesota. Minnesota Rules part 1309.0301, subpart 2 amends IRC Table R301.2(1) ("Climatic and Geographic Design Criteria") to pre-fill "ICE BARRIER UNDERLAYMENT REQUIRED[h] ... Yes" for the entire state. Corroborated by a Minnesota DLI consumer guidance sheet ("Asphalt Shingle Roofing and the 2020 Minnesota Residential Code," Construction Codes and Licensing Division): "Ice barrier protection at eaves is required in Minnesota," extending "from the eave's edge to a point at least 24 inches inside the exterior wall line of the building." Bloomington has no authority to opt out of this (Minn. Stat. § 326B.121, subd. 2(c)). Garages: Bloomington's own FAQ adds a garage-specific answer: "Is an ice barrier required for roofing or reroofing a garage? An ice barrier is required for all attached garages and for all detached heated garages" -- implying detached unheated garages are exempt. Because ice-barrier applicability is state-governed code content that cities cannot vary, confirm the treatment of a detached unheated garage with the Building and Inspections Division before bidding it either way.
City of Brooklyn Park, Minnesota - Building Inspections Division (City of Brooklyn Park, Minnesota)
STATE-GOVERNED, and independently restated by Brooklyn Park's own published guidance. Minnesota Rules part 1309.0301, subpart 2 amends IRC Table R301.2(1) to pre-fill "ICE BARRIER UNDERLAYMENT REQUIRED[h] ... Yes" for the entire state. Brooklyn Park's own Residential Reroofing guide, under "ICE BARRIER MEMBRANE UNDERLAYMENTS," states verbatim: "An ice barrier that consists of at least two layers of underlayment cemented together or of a self-adhering polymer modified bitumen sheet, shall be used in lieu of normal underlayment, and extend from the eave edge to a point at least 24 inches horizontally inside the exterior wall line of the building. (R905.1.2)" It further addresses reroofing over an existing adhered ice barrier: "Where the existing roof assembly includes an ice barrier membrane that is adhered to the roof deck, the existing ice barrier membrane shall be permitted to remain in place and covered with an additional layer of ice barrier membrane. (R908.3)"
City of Burnsville, Minnesota - Building Inspections Department (City of Burnsville, Minnesota)
STATE-GOVERNED, NOT CITY-SET -- applies identically in Burnsville as everywhere else in Minnesota (see adopted_code). Minnesota Rules part 1309.0301, subpart 2 amends IRC Table R301.2(1) to pre-fill "ICE BARRIER UNDERLAYMENT REQUIRED[h] ... Yes" for the entire state; footnote h cross-references IRC Sections R905.1.2, R905.2.7, R905.4.3.1, R905.5.3.1, R905.6.3.1, R905.7.3.1 and R905.8.3.1. Locally, the City of Burnsville's own "Re-Roofing Requirements" handout states, under a heading "Ice Barrier Required!!!": "The Minnesota building code requires that an approved ice barrier underlayment be installed from your roofs edge to a point at least 24 inches past the exterior wall line. This applies to all portions of your roof, including attached heated or un-heated garages, covered porches, bays, fireplace enclosures and similar areas" -- and requires photographic proof of the ice barrier before final inspection.
City of Coon Rapids, Minnesota - Building Inspections Division (City of Coon Rapids, Minnesota)
The City of Coon Rapids' own "Residential Roofing" handout states, under "ICE BARRIERS R905.1.2," "All dwellings, structures attached to dwellings, and all conditioned (heated and/or cooled) structures, require ice barrier. The ice barrier shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet shall be used in place of normal underlayment and extend from the lowest edges of all roof surfaces to a point not less than 24 inches inside the exterior wall line of the building. On roofs with slope equal to or greater than 8:12, the ice barrier shall also be applied not less than 36 inches measured along the roof slope from the eave edge of the building. Exception: Detached accessory structures not containing conditioned floor area." This matches Minnesota Rules part 1309.0301, subpart 2, which pre-fills "ICE BARRIER UNDERLAYMENT REQUIRED" statewide.
City of Duluth, Minnesota - Construction Services & Inspections (City of Duluth, Minnesota)
Minn. R. 1309.0301, subp. 2, which amends IRC Table R301.2(1) (Climatic and Geographic Design Criteria) statewide, lists "Ice Barrier Underlayment Required" as "Yes," per footnote h, "in accordance with Sections R905.1.2, R905.2.7, R905.4.3.1, R905.5.3.1, R905.6.3.1, R905.7.3.1, and R905.8.3.1, where there has been a history of local damage from the effects of ice damming." Duluth administers this table as part of its adoption of the Minnesota State Building Code.
City of Eden Prairie, Minnesota - Building Inspections (City of Eden Prairie, Minnesota)
STATE-GOVERNED, NOT CITY-SET — the requirement applies identically in Eden Prairie as everywhere else in Minnesota. Minnesota Rules part 1309.0301, subpart 2 amends IRC Table R301.2(1) ("Climatic and Geographic Design Criteria") to pre-fill "ICE BARRIER UNDERLAYMENT REQUIRED[h] ... Yes" for the entire state. The Minnesota Department of Labor and Industry's guidance sheet, "Asphalt Shingle Roofing and the 2020 Minnesota Residential Code," describes what satisfies it: an ice barrier "may be at least two layers of underlayment cemented together or a self-adhering polymer modified bitumen sheet," extending from the eave edge to a point at least 24 inches inside the exterior wall line of the building. Eden Prairie has no authority to opt out (Minn. Stat. 326B.121, subd. 1 makes the State Building Code the standard that applies statewide and provides that it supersedes the building code of any municipality, and subd. 2(c) bars a municipality from requiring building code provisions regulating components or systems of a structure that differ from the State Building Code). Garage and detached-accessory-structure applicability is worded differently by different Minnesota cities — Apple Valley exempts "unheated detached accessory structures" while Maplewood and Minnetonka exempt detached accessory buildings with no heated qualifier — so confirm that specific case with the building department rather than assuming a blanket detached-garage exemption.
City of Edina, Minnesota - Building Inspections Division (City of Edina, Minnesota)
STATE-GOVERNED, NOT CITY-SET — the requirement applies identically in Edina as everywhere else in Minnesota. Minnesota Rules part 1309.0301, subpart 2 amends IRC Table R301.2(1) ("Climatic and Geographic Design Criteria") to pre-fill "ICE BARRIER UNDERLAYMENT REQUIRED[h] ... Yes" for the entire state. The Minnesota Department of Labor and Industry's guidance sheet, "Asphalt Shingle Roofing and the 2020 Minnesota Residential Code," describes what satisfies it: an ice barrier "may be at least two layers of underlayment cemented together or a self-adhering polymer modified bitumen sheet," extending from the eave edge to a point at least 24 inches inside the exterior wall line of the building. Edina has no authority to opt out (Minn. Stat. 326B.121, subd. 1 makes the State Building Code the standard that applies statewide and provides that it supersedes the building code of any municipality, and subd. 2(c) bars a municipality from requiring building code provisions regulating components or systems of a structure that differ from the State Building Code). Garage and detached-accessory-structure applicability is worded differently by different Minnesota cities — Apple Valley exempts "unheated detached accessory structures" while Maplewood and Minnetonka exempt detached accessory buildings with no heated qualifier — so confirm that specific case with the building department rather than assuming a blanket detached-garage exemption.
City of Lakeville, Minnesota - Building Inspections Division (City of Lakeville, Minnesota)
Lakeville's Residential Re-Roofing Guide states, under "GENERAL BUILDING CODE REQUIREMENTS": "Ice and water protection shall comply with ASTM D 1970 and be provided at the eves extending 24 inches inside the exterior wall line. Not required on detached unheated structures. Existing membrane may remain in place but must be covered with new." This mirrors the statewide requirement built into Minnesota Rules part 1309.0301, subpart 2 (amending IRC Table R301.2(1) to pre-fill "Yes" for ice barrier underlayment statewide). Lakeville's own document supplies the garage/outbuilding nuance: ice-and-water protection is not required on detached unheated structures.
City of Mankato, Minnesota - Building Inspections (City of Mankato, Minnesota)
STATE-GOVERNED, NOT CITY-SET — the requirement applies identically in Mankato as everywhere else in Minnesota. Minnesota Rules part 1309.0301, subpart 2 amends IRC Table R301.2(1) ("Climatic and Geographic Design Criteria") to pre-fill "ICE BARRIER UNDERLAYMENT REQUIRED[h] ... Yes" for the entire state. The Minnesota Department of Labor and Industry's guidance sheet, "Asphalt Shingle Roofing and the 2020 Minnesota Residential Code," describes what satisfies it: an ice barrier "may be at least two layers of underlayment cemented together or a self-adhering polymer modified bitumen sheet," extending from the eave edge to a point at least 24 inches inside the exterior wall line of the building. Mankato has no authority to opt out (Minn. Stat. 326B.121, subd. 1 makes the State Building Code the standard that applies statewide and provides that it supersedes the building code of any municipality, and subd. 2(c) bars a municipality from requiring building code provisions regulating components or systems of a structure that differ from the State Building Code). Garage and detached-accessory-structure applicability is worded differently by different Minnesota cities — Apple Valley exempts "unheated detached accessory structures" while Maplewood and Minnetonka exempt detached accessory buildings with no heated qualifier — so confirm that specific case with the building department rather than assuming a blanket detached-garage exemption.
City of Maple Grove, Minnesota - Building Inspection Services (City of Maple Grove, Minnesota)
STATE-GOVERNED, NOT CITY-SET -- applies identically in Maple Grove as everywhere else in Minnesota. Minnesota Rules part 1309.0301, subpart 2 amends IRC Table R301.2(1) ("Climatic and Geographic Design Criteria") to pre-fill "ICE BARRIER UNDERLAYMENT REQUIRED[h] ... Yes" for the entire state -- footnote h ties this to IRC Sections R905.1.2 etc. "where there has been a history of local damage from the effects of ice damming," a determination Minnesota has made statewide by rule. Corroborated by a Minnesota DLI consumer guidance sheet: "Ice barrier protection at eaves is required in Minnesota," extending "from the eave's edge to a point at least 24 inches inside the exterior wall line of the building." Maple Grove has no authority to opt out of this (Minn. Stat. § 326B.121, subd. 2(c)). The literal installation-extent text of R905.1.2 itself, which Minnesota does not amend, could not be obtained verbatim (ICC paywall); the DLI sheet's restated figures are cited instead of the raw code section for that reason. On garages: Maple Grove's own official roofing handout ("Roofing," Building Department, Rev 4/7/2021, maplegrovemn.gov) states the exception as: "An ice and water barrier is required on all roofs except for detached accessory buildings (garages)" -- with no heated/conditioned qualifier at all. This is broader than the framing used by other Minnesota cities: Bloomington, MN's FAQ requires it "for all attached garages and for all detached HEATED garages" (i.e. only unheated detached garages are exempt), and an older Plymouth, MN handout ties the exemption to structures with "no conditioned floor areas" -- both narrower than Maple Grove's blanket "garages" wording. Because ice-barrier applicability is state-governed code content that no city can vary, Maple Grove's own handout may be overstating the exemption relative to the actual state rule (which appears to hinge on conditioned/heated status, not simply detached-vs-attached) -- a roofer relying on Maple Grove's literal wording for a detached, HEATED garage could be under-installing required ice barrier. Check the current R905.1.2 text before relying on the handout's wording for a heated detached garage.
City of Maplewood, Minnesota - Building Inspections (City of Maplewood, Minnesota)
Maplewood's roofing handout states: "An ice and water barrier is required on all roofs except for detached accessory buildings (garages). The barrier may be at least two layers of underlayment cemented together or a self-adhering polymer modified bitumen sheet... The ice and water barrier must extend from the edge of the eaves to a point at least 24 inches inside the exterior wall line of the building. Ice and water barriers are not required along the rakes or in valleys." This is state-governed content rather than a city choice: Minnesota Rules part 1309.0301, subpart 2 amends IRC Table R301.2(1) to read "ICE BARRIER UNDERLAYMENT REQUIRED[h] ... Yes" for the whole state, so the requirement survives the handout's 2015 revision date. WATCH THE GARAGE WORDING. Maplewood's exemption is written for "detached accessory buildings (garages)" with no heated or conditioned qualifier, whereas Apple Valley, Minnesota words the same exemption as applying to "unheated detached accessory structures" and Bloomington, Minnesota frames it around heated detached garages. Because applicability here is state code content rather than a municipal choice, confirm garage-specific applicability with the Building Department at 651-249-2300 rather than relying on a blanket detached-garage exemption.
City of Minneapolis, Minnesota - Community Planning & Economic Development, Development Services (Building Inspections) (City of Minneapolis, Minnesota)
STATE-GOVERNED, NOT CITY-SET -- applies identically in Minneapolis as everywhere else in Minnesota. Minnesota Rules part 1309.0301, subpart 2 amends IRC Table R301.2(1) ("Climatic and Geographic Design Criteria") to pre-fill "ICE BARRIER UNDERLAYMENT REQUIRED[h] ... Yes" for the entire state -- footnote h ties this to IRC Sections R905.1.2 etc. "where there has been a history of local damage from the effects of ice damming," a determination Minnesota has made statewide by rule rather than leaving to municipal option. Minneapolis has no authority to opt out of this (Minn. Stat. § 326B.121, subd. 2(c)). The literal installation-extent text of R905.1.2 itself is unamended bare 2018 IRC text that could not be obtained verbatim (ICC paywall) and is therefore not restated here.
City of Minnetonka, Minnesota - Building Inspections Division (City of Minnetonka, Minnesota)
Minnetonka states it in its own words: "An ice and water barrier is required on all roofs except for detached accessory buildings. The barrier may be at least two layers of underlayment cemented together or a self-adhering polymer modified bitumen sheet." Note the City's exemption is written for detached accessory buildings with no heated or conditioned qualifier, where Apple Valley, Minnesota words the same exemption as applying to "unheated detached accessory structures." The requirement itself is state-governed: Minnesota Rules part 1309.0301, subpart 2 amends IRC Table R301.2(1) to read "ICE BARRIER UNDERLAYMENT REQUIRED[h] ... Yes" for the whole state. The barrier is also what the City's single inspection checks — see the mid-roof inspection field.
City of Moorhead, Minnesota - Building Inspections (City of Moorhead, Minnesota)
STATE-GOVERNED, NOT CITY-SET — the requirement applies identically in Moorhead as everywhere else in Minnesota. Minnesota Rules part 1309.0301, subpart 2 amends IRC Table R301.2(1) ("Climatic and Geographic Design Criteria") to pre-fill "ICE BARRIER UNDERLAYMENT REQUIRED[h] ... Yes" for the entire state. The Minnesota Department of Labor and Industry's guidance sheet, "Asphalt Shingle Roofing and the 2020 Minnesota Residential Code," describes what satisfies it: an ice barrier "may be at least two layers of underlayment cemented together or a self-adhering polymer modified bitumen sheet," extending from the eave edge to a point at least 24 inches inside the exterior wall line of the building. Moorhead has no authority to opt out (Minn. Stat. 326B.121, subd. 1 makes the State Building Code the standard that applies statewide and provides that it supersedes the building code of any municipality, and subd. 2(c) bars a municipality from requiring building code provisions regulating components or systems of a structure that differ from the State Building Code). Garage and detached-accessory-structure applicability is worded differently by different Minnesota cities — Apple Valley exempts "unheated detached accessory structures" while Maplewood and Minnetonka exempt detached accessory buildings with no heated qualifier — so confirm that specific case with the building department rather than assuming a blanket detached-garage exemption.
City of Plymouth, Minnesota - Building Inspection Division (City of Plymouth, Minnesota)
STATE-GOVERNED, NOT CITY-SET -- applies identically in Plymouth as everywhere else in Minnesota. Minnesota Rules part 1309.0301, subpart 2 amends IRC Table R301.2(1) ("Climatic and Geographic Design Criteria") to pre-fill "ICE BARRIER UNDERLAYMENT REQUIRED[h] ... Yes" for the entire state. A Minnesota DLI consumer guidance sheet ("Asphalt Shingle Roofing and the 2020 Minnesota Residential Code," Construction Codes and Licensing Division) hosted on Plymouth's own website states directly: "Ice barrier protection at eaves is required in Minnesota," using "an ice barrier that consists of at least two layers of underlayment cemented together or of a self-adhering polymer modified bitumen sheet... extend[ing] from the eave's edge to a point at least 24 inches inside the exterior wall line of the building." On slopes between 2:12 and 4:12, the sheet notes "a double underlayment application in accordance with Section R905.2.7" is required due to greater ice-dam risk. Plymouth has no authority to opt out of this (Minn. Stat. § 326B.121, subd. 2(c)). GARAGE NUANCE: an older (2015-vintage, drafted against the now-superseded 2015 MSBC/2012 IRC -- staleness caveat applies) Plymouth "Reroofing Information Sheet" states the ice-barrier exception as: "Detached accessory structures (garages and storage buildings) that contain no conditioned floor areas are not required to have an ice barrier" -- i.e. the exemption turns on CONDITIONED status, not simply attached/detached. The Bloomington, MN record frames it the same way ("required for all attached garages and for all detached HEATED garages"), while Maple Grove, MN's own current roofing handout exempts "detached accessory buildings (garages)" with no heated/conditioned qualifier at all. Because ice-barrier applicability is state-governed code content rather than a city choice, confirm garage-specific applicability with the Building Inspection Division before relying on a blanket detached-garage exemption.
City of Rochester, Minnesota - Building Safety Division (City of Rochester, Minnesota)
STATE-GOVERNED, NOT CITY-SET -- applies identically in Rochester as everywhere else in Minnesota, because Rochester adopts the Minnesota State Building Code without local amendment (see adopted_code). Minnesota Rules part 1309.0301, subpart 2 amends IRC Table R301.2(1) to pre-fill "ICE BARRIER UNDERLAYMENT REQUIRED[h] ... Yes" for the entire state; footnote h cross-references IRC Sections R905.1.2, R905.2.7, R905.4.3.1, R905.5.3.1, R905.6.3.1, R905.7.3.1 and R905.8.3.1 for the applicable ice-barrier standard. Rochester has no authority to opt out of this (Minn. Stat. § 326B.121, subd. 2(c)). GARAGE NUANCE: because this is a state-level pre-filled table entry, no Rochester-specific garage exemption is established in this record; confirm garage-specific applicability with Building Safety before relying on any blanket exemption.
City of Roseville, Minnesota - Building Division (City of Roseville, Minnesota)
STATE-GOVERNED, NOT CITY-SET — the requirement applies identically in Roseville as everywhere else in Minnesota. Minnesota Rules part 1309.0301, subpart 2 amends IRC Table R301.2(1) ("Climatic and Geographic Design Criteria") to pre-fill "ICE BARRIER UNDERLAYMENT REQUIRED[h] ... Yes" for the entire state. The Minnesota Department of Labor and Industry's guidance sheet, "Asphalt Shingle Roofing and the 2020 Minnesota Residential Code," describes what satisfies it: an ice barrier "may be at least two layers of underlayment cemented together or a self-adhering polymer modified bitumen sheet," extending from the eave edge to a point at least 24 inches inside the exterior wall line of the building. Roseville has no authority to opt out (Minn. Stat. 326B.121, subd. 1 makes the State Building Code the standard that applies statewide and provides that it supersedes the building code of any municipality, and subd. 2(c) bars a municipality from requiring building code provisions regulating components or systems of a structure that differ from the State Building Code). Garage and detached-accessory-structure applicability is worded differently by different Minnesota cities — Apple Valley exempts "unheated detached accessory structures" while Maplewood and Minnetonka exempt detached accessory buildings with no heated qualifier — so confirm that specific case with the building department rather than assuming a blanket detached-garage exemption.
City of Saint Paul, Minnesota - Department of Safety and Inspections (DSI) (City of Saint Paul, Minnesota)
STATE-GOVERNED, NOT CITY-SET -- applies identically in Saint Paul as everywhere else in Minnesota. Minnesota Rules part 1309.0301, subpart 2 amends IRC Table R301.2(1) ("Climatic and Geographic Design Criteria") to pre-fill "ICE BARRIER UNDERLAYMENT REQUIRED[h] ... Yes" for the entire state -- footnote h ties this to IRC Sections R905.1.2 etc. "where there has been a history of local damage from the effects of ice damming," a determination Minnesota has made statewide by rule rather than leaving to municipal option. Saint Paul has no authority to opt out of this (Minn. Stat. § 326B.121, subd. 2(c)). The literal installation-extent text of R905.1.2 itself is unamended base 2018 IRC text and is not reproduced here; refer to the 2018 IRC for the installation extent.
City of Shakopee, Minnesota - Building Inspections (City of Shakopee, Minnesota)
STATE-GOVERNED, NOT CITY-SET — the requirement applies identically in Shakopee as everywhere else in Minnesota. Minnesota Rules part 1309.0301, subpart 2 amends IRC Table R301.2(1) ("Climatic and Geographic Design Criteria") to pre-fill "ICE BARRIER UNDERLAYMENT REQUIRED[h] ... Yes" for the entire state. The Minnesota Department of Labor and Industry's guidance sheet, "Asphalt Shingle Roofing and the 2020 Minnesota Residential Code," describes what satisfies it: an ice barrier "may be at least two layers of underlayment cemented together or a self-adhering polymer modified bitumen sheet," extending from the eave edge to a point at least 24 inches inside the exterior wall line of the building. Shakopee has no authority to opt out (Minn. Stat. 326B.121, subd. 1 makes the State Building Code the standard that applies statewide and provides that it supersedes the building code of any municipality, and subd. 2(c) bars a municipality from requiring building code provisions regulating components or systems of a structure that differ from the State Building Code). Garage and detached-accessory-structure applicability is worded differently by different Minnesota cities — Apple Valley exempts "unheated detached accessory structures" while Maplewood and Minnetonka exempt detached accessory buildings with no heated qualifier — so confirm that specific case with the building department rather than assuming a blanket detached-garage exemption.
City of St. Cloud, Minnesota - Building Safety Division (City of St. Cloud, Minnesota)
STATE-GOVERNED, and restated in St. Cloud's own guidance. Minnesota Rules part 1309.0301, subpart 2 amends IRC Table R301.2(1) to pre-fill an ice-barrier-underlayment requirement statewide. St. Cloud's own "Residential Reroof" handout (Building Safety Department), citing R905.1.2, states: "Ice/water barrier is required on all roofs, except for a detached accessory structure with no conditioned floor area. Ice/water barrier is required to consist of at least two layers of underlayment cemented together or a self-adhering polymer modified bitumen sheet. The ice/water barrier shall be used in place of normal underlayment and extend from the lowest edge of all roof surfaces to a point at least 24 inches inside the exterior wall line of the building. On roofs with a slope equal to or greater than 8/12, the ice barrier shall also be applied not less than 36 [inches] measured along the roof slope from the eave edge of the building."
City of St. Louis Park, Minnesota - Building and Energy Department (City of St. Louis Park, Minnesota)
STATE-GOVERNED, NOT CITY-SET — the requirement applies identically in St. Louis Park as everywhere else in Minnesota. Minnesota Rules part 1309.0301, subpart 2 amends IRC Table R301.2(1) ("Climatic and Geographic Design Criteria") to pre-fill "ICE BARRIER UNDERLAYMENT REQUIRED[h] ... Yes" for the entire state. The Minnesota Department of Labor and Industry's guidance sheet, "Asphalt Shingle Roofing and the 2020 Minnesota Residential Code," describes what satisfies it: an ice barrier "may be at least two layers of underlayment cemented together or a self-adhering polymer modified bitumen sheet," extending from the eave edge to a point at least 24 inches inside the exterior wall line of the building. St. Louis Park has no authority to opt out (Minn. Stat. 326B.121, subd. 1 makes the State Building Code the standard that applies statewide and provides that it supersedes the building code of any municipality, and subd. 2(c) bars a municipality from requiring building code provisions regulating components or systems of a structure that differ from the State Building Code). Garage and detached-accessory-structure applicability is worded differently by different Minnesota cities — Apple Valley exempts "unheated detached accessory structures" while Maplewood and Minnetonka exempt detached accessory buildings with no heated qualifier — so confirm that specific case with the building department rather than assuming a blanket detached-garage exemption.
City of Woodbury, Minnesota - Building Inspections Division (City of Woodbury, Minnesota)
STATE-GOVERNED, NOT CITY-SET -- applies identically in Woodbury as everywhere else in Minnesota, because Woodbury adopts the Minnesota State Building Code without local amendment on this point (see adopted_code). Minnesota Rules part 1309.0301, subpart 2 amends IRC Table R301.2(1) to pre-fill "ICE BARRIER UNDERLAYMENT REQUIRED[h] ... Yes" for the entire state; footnote h cross-references IRC Sections R905.1.2, R905.2.7, R905.4.3.1, R905.5.3.1, R905.6.3.1, R905.7.3.1 and R905.8.3.1 for the applicable ice-barrier standard. Woodbury has no authority to opt out of this (Minn. Stat. § 326B.121, subd. 2(c)). Woodbury's own Roofing Information Handout independently corroborates an ice-dam rule locally: "Ice dam protection is required on all roofs and shall extend from the edge of the roof 24" past the exterior wall line." GARAGE NUANCE: because the state table entry is a uniform pre-fill, no Woodbury-specific garage exemption has been on record; confirm garage-specific applicability with Building Inspections before relying on any blanket exemption.
Ice barrier required — Missouri (14)
Cass County Building Codes Department (Cass County, Missouri)
Cass County Building Codes Department amendments to the 2006 I-Codes ("Last Updated December 28, 2009," effective 1/1/2010) insert values into IRC Table R301.2(1), Climatic and Geographic Design Criteria, including "Ice Barrier Underlayment ... Yes." The county's amendment document does not separately amend IRC Chapter 9 (Roof Assemblies), so the requirement operates under the standard, unamended 2006 IRC ice-barrier extent provision (membrane extending from the lowest roof edge to not less than 24 inches inside the exterior wall line).
City of Belton - Community Development Department (City of Belton, Missouri)
City of Belton UDC Sec. 10-5, "Adoption of International Residential Code for One- and Two-Family Dwellings, 2018 edition, with local amendments" (Ord. No. 2022-4738, § 2, adopted 9-27-2022), amends Table R301.2(1), Climatic and Geographic Design Criteria, inserting "Ice Barrier required - Yes." The City's Inspection Guidebook separately lists ice and water shield as an inspected roofing component ("Sheathing, ice and water shield and underlayment, drip edge, valleys, and venting installed to adopted codes"). Belton's Sec. 10-5 amendments do not separately touch IRC Section R905 (Roof Assemblies), so the standard 2018 IRC ice-barrier extent provision (membrane extending from the lowest roof edge to not less than 24 inches inside the exterior wall line) applies unamended.
City of Blue Springs - Community Development Department (Codes Administration Division) (City of Blue Springs, Missouri)
Table R301.2(1) Climatic and Geographic Design Criteria, as amended in the adopted International Residential Code, states: "Ice Barrier Underlayment Required: Yes." (Ordinance No. 5480, amending Code of Ordinances Section 500.010(A)(7)(a), adopting the 2024 IRC, passed by the Blue Springs City Council February 18, 2026.)
City of Florissant, Missouri - Department of Public Works (Building Department) (City of Florissant, Missouri)
Florissant's Table R301.2(1) Climatic and Geographic Design Criteria (as amended) lists "Ice Barrier Underlayment Required" as "YES," with the table's own footnote h stating: "In accordance with Sections R905.1.2, R905.4.3.1, R905.5.3.1, R905.6.3.1, R905.7.3.1 and R905.8.3.1: The jurisdiction shall fill in this part of the table with 'YES.' Exemption applies to houses built after January 1, 2023." The table repeats this in expanded form: "Ice Shield Underlayment Required - YES." So ice barrier/ice-and-water-shield underlayment IS required as a blanket rule EXCEPT for houses built after January 1, 2023, which are exempt -- a Florissant-specific new-construction carve-out that a roofer should confirm against the house's construction/permit date before assuming the requirement applies.
City of Gladstone, Missouri - Community Development Department (Building and Construction Division) (City of Gladstone, Missouri)
"Ice barrier is require[d] for all roofing and reroofing. Ice barrier shall consist of 2-layers of underlayment cemented together or a self-adhering polymer modified bitumen sheet. Ice barrier shall extend from the lowest edges of all roof surfaces to a point at least twenty-four (24) inches inside the exterior wall line of the building." Stated identically for both Residential and Commercial, with no history-of-ice-damming trigger language -- a blanket requirement on every roof/reroof. Corroborated by Table R301.2 of Chapter 200 (BACO), adopting the 2021 IRC, which lists "Ice Barrier Underlayment Required: Yes."
City of Grain Valley - Community Development Department (City of Grain Valley, Missouri)
Section 500.100.C.4, Table R301.2(1) as amended, states: "Ice Shield Underlayment Required: Yes." (City of Grain Valley Code of Ordinances, adopting the 2018 IRC effective May 1, 2021, per Ordinance No. 2550, 7-26-2021.)
City of Grandview - Building Services Division (City of Grandview, Missouri)
The city's own amended Table R301.2(1), codified at Sec. 10-25(2) (Residential code amendments, within the 2018 IRC adopted at Sec. 10-23(a)(2), most recently amended by Ord. No. 7282, §§ 1-8, 1-12-2021), lists "Ice Barrier Underlayment Required ... Yes" among the table's climatic/geographic design criteria entries.
City of Independence, Missouri - Building Inspections Division (City of Independence, Missouri)
Table R301.2(1) Climatic and Geographic Design Criteria, as amended by the ordinance adopting the 2018 IRC (effective 1/1/2019), states: "Ice Barrier Underlayment: Yes, installed as required by section 905.1.2." Section R905.1.2 requires the ice barrier to extend from the lowest edges of the roof to a point not less than 24 inches inside the exterior wall line of the building.
City of Kansas City, Missouri - City Planning & Development Department (City of Kansas City, Missouri)
Kansas City's amended IRC Table R301.2(1) (Code of Ordinances Sec. 18-57, Article III, Residential Code) lists "ICE BARRIER UNDERLAYMENT REQUIRED: Yes" (Winter Design Temp 6F, Air Freezing Index 1000). Under the unamended 2018 IRC R905.1.2 baseline this extends from the eave edge to 24 in. inside the exterior wall line on all eaves. Architect-verified directly on the current municode codification, 2026-07-19.
City of Lee's Summit - Development Services Department (City of Lee's Summit, Missouri)
The city's own Table R301.2(1) data entry, codified in Sec. 7-902 of the Lee's Summit Building Code (Ord. No. 8584, § 1, adopted 3-19-2019, effective 4-1-2019), lists "Ice Barrier Underlayment Requirement ... Yes." Section R905.1.2 (Ice barriers), which supplies the trigger language for that "Yes" -- "an ice barrier ... shall be installed ... and shall extend from the lowest edges of all roof surfaces to a point not less than 24 inches inside the exterior wall line of the building" -- is adopted as part of the 2018 IRC (Sec. 7-900) and is not amended or altered anywhere in Article IX.
City of Liberty - Building Division (City of Liberty, Missouri)
"2018 IBC Section 1507.6.4 Ice barrier. In areas where there has been a history of ice forming along the eaves causing a backup of water, an ice barrier that consists of at least two layers of underlayment cemented together or of a self-adhering polymer-modified bitumen sheet shall be used in lieu of normal underlayment and extend from the lowest edges of all roof surfaces to a point at least 24 inches inside the exterior wall line of the building. Exception: Detached accessory structures that contain no conditioned floor area." (City of Liberty Planning and Development Department, "Ice Barrier Requirements," updated 3/5/2021; the city states it "enforces Chapter 9 of the IRC and Chapter 15 of the IBC as it pertains to 'Ice and Water Shield' requirements... as written.") Corroborated by Table R301.2 of Ordinance No. 11358 (adopting the 2018 IRC, passed/approved 2/22/2021), which lists "Ice Barrier Underlayment Required: Yes."
City of North Kansas City - Community Development Department (City of North Kansas City, Missouri)
"Table R301.2(l) is amended as follows: ... Ice Shield Underlayment Required: Yes" (North Kansas City Code of Ordinances Sec. 15.26.020, Amendments to Residential Code, amending the 2018 IRC Table R301.2(1); section last modified by Ord. No. 9743, 11-4-2025). The amendment does not condition the "Yes" on elevation, slope, or any other factor beyond the citywide table entry.
City of Raytown - Community Development Department (Building Inspections) (City of Raytown, Missouri)
The city's own amended Table R301.2(1), codified at Sec. 8-137 (Amendments to residential code, within the 2018 IRC adopted at Sec. 8-136, most recently amended by Ord. No. 5617-19, § 1, 10-15-2019), lists "Ice Barrier Underlayment Required = YES" among the table's climatic/geographic design criteria entries.
Clay County - Planning & Zoning Department (Clay County, Missouri)
The same letter states: "Section 905.2.7.1 - Ice Barrier - Table 301.2(1) requires each jurisdiction to indicate through its weather history the need for ice barrier. Clay County does require the adherence of an ice barrier application (one of two methods in the code)." The attached 2012 IRC R905.2.7.1 text furnished in the same document reads: "In areas where there has been a history of ice forming along the eaves causing a backup of water..., an ice barrier that consists of a least two layers of underlayment cemented together or of a self-adhering polymer modified bitumen sheet shall be used in lieu of normal underlayment and extend from the lowest edges of all roof surfaces to a point at least 24 inches (610 mm) inside the exterior wall line of the building. Exception: Detached accessory structures that contain no conditioned floor area."
Ice barrier required — Nebraska (4)
City of Bellevue - Permits and Inspection Division (City of Bellevue, Nebraska)
Bellevue's amended IRC Table R301.2, Climatic and Geographic Design Criteria (Bellevue City Code § 8-18.6(B), Ord. 4033, passed 5-4-2021), lists "Ice Barrier Required" as "YES" for the city.
City of Lincoln - Building & Safety Department (City of Lincoln, Nebraska)
"Ice Barrier is required for all spaces. (R905.1.2) The self-adhering sheet shall extend from lowest edges of all roof surfaces to a point not less than 24” inside the exterior wall line of the building." (City of Lincoln Building & Safety, Re-Roof Policy, rev. 12/10/2021). Corroborated by the city's own amended climate-criteria table, which lists "Ice Barrier Underlayment Required: Yes" (Lincoln Municipal Code 20.12.140, Table R301.2 Amended; Climatic and Geographic Design Criteria, Ord. 21820 §5, Dec. 15, 2025).
City of Papillion - Building & Fire Safety Department (City of Papillion, Nebraska)
"Ice and Water Shield (905.1.2): Two layers of Ice and Water shield are required for all roofs." (City of Papillion Roofing Requirements handout, per 2018 IRC Chapter 9). Consistent with the city's amended IRC Table R301.2(1), which lists "Ice Barrier Underlayment Required: Yes" for Papillion (Papillion Municipal Code § 92-15(B), Ordinance No. 1934). The handout's "all roofs" identifies which BUILDINGS the requirement covers, not how far up the slope the barrier runs — the city's ordinance does not amend R905.1.2 itself, so the standard extent (from the eave edge to 24 in. inside the exterior wall line) governs. Confirm extent with the Building Division on unusual roof geometry.
Lancaster County - Building & Safety (City of Lincoln) (Lancaster County, Nebraska)
"Ice Barrier is required for all spaces. (R905.1.2) The self-adhering sheet shall extend from lowest edges of all roof surfaces to a point not less than 24” inside the exterior wall line of the building." (Re- Roof Policy, rev. 12/10/2021, issued by the City of Lincoln Building & Safety Department under the joint standard: "The City of Lincoln & Lancaster County has adopted and enforces all sections of the 2018 International Residential Code (IRC)... the respective adopted amendments." No separate Lancaster County building department exists; see the paired City of Lincoln, Nebraska record).
Ice barrier required — North Dakota (1)
Ice barrier required — Ohio (21)
City of Akron, Ohio - Building Permits and Inspections (City of Akron, Ohio)
SET BY STATE RULE -- required in Akron exactly as everywhere else in Ohio, because Ohio makes the ice-damming determination statewide by rule rather than leaving it to local option. RCO Table 301.2(1) pre-fills "Ice Barrier Underlayment Required" as "Yes" for the whole state, with footnote (h): "In accordance with Sections 905.1.2, 905.4.3.1, 905.5.3.1, 905.6.3.1, 905.7.3.1 and 905.8.3.1, all jurisdictions in Ohio have a history of local damage from the effects of ice damming." RCO Section 905.1.2 (Ice barriers) provides, verbatim: "In areas where there has been a history of ice forming along the eaves causing a backup of water as designated in Table 301.2(1), an ice barrier shall be installed for asphalt shingles, metal roof shingles, mineral-surfaced roll roofing, slate and slate-type shingles, wood shingles and wood shakes. The ice barrier shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet shall be used in place of normal underlayment and extend from the lowest edges of all roof surfaces to a point not less than 24 inches (610 mm) inside the exterior wall line of the building. The 24 inch measurement shall be along the slope of the roof from the point where the projected outside face of the wall intersects the roof deck. On roofs with slope equal to or greater than eight units vertical in 12 units horizontal (67-percent slope), the ice barrier shall also be applied not less than 36 inches measured along the roof slope from the eave edge of the building." Exception, verbatim: "Detached accessory structures and roof assemblies terminating at a vertical wall over unconditioned floor areas."
City of Canton, Ohio - Building/Code Enforcement Division (City of Canton, Ohio)
SET BY STATE RULE -- applies identically in Canton as everywhere else in Ohio. RCO Table 301.2(1) pre-fills "Ice Barrier Underlayment Required" as "Yes" for the whole state, with footnote (h) reciting that "all jurisdictions in Ohio have a history of local damage from the effects of ice damming." RCO Section 905.1.2 (Ice barriers) then requires an ice barrier for asphalt shingles and other listed coverings, consisting of not fewer than two layers of cemented underlayment or a self-adhering polymer-modified bitumen sheet, extending not less than 24 inches inside the exterior wall line (36 inches on slopes of 8:12 or greater). Exception: "Detached accessory structures and roof assemblies terminating at a vertical wall over unconditioned floor areas."
City of Cincinnati, Ohio - Department of Buildings & Inspections (City of Cincinnati, Ohio)
SET BY STATE RULE - required in Cincinnati exactly as everywhere else in Ohio, because Ohio makes the ice-damming determination statewide by rule rather than leaving it to local option. RCO Table 301.2(1) pre-fills "Ice Barrier Underlayment Required" as "Yes" for the whole state, with footnote (h): "In accordance with Sections 905.1.2, 905.4.3.1, 905.5.3.1, 905.6.3.1, 905.7.3.1 and 905.8.3.1, all jurisdictions in Ohio have a history of local damage from the effects of ice damming." RCO Section 905.1.2 (Ice barriers) then provides, verbatim: "In areas where there has been a history of ice forming along the eaves causing a backup of water as designated in Table 301.2(1), an ice barrier shall be installed for asphalt shingles, metal roof shingles, mineral-surfaced roll roofing, slate and slate-type shingles, wood shingles and wood shakes. The ice barrier shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet shall be used in place of normal underlayment and extend from the lowest edges of all roof surfaces to a point not less than 24 inches (610 mm) inside the exterior wall line of the building. The 24 inch measurement shall be along the slope of the roof from the point where the projected outside face of the wall intersects the roof deck. On roofs with slope equal to or greater than eight units vertical in 12 units horizontal (67-percent slope), the ice barrier shall also be applied not less than 36 inches measured along the roof slope from the eave edge of the building." The final two sentences are Ohio-specific additions beyond the base 2018 IRC text. Exception: "Detached accessory structures and roof assemblies terminating at a vertical wall over unconditioned floor areas" (the italicised clause is also an Ohio addition).
City of Cleveland Heights, Ohio - Division of Building (City of Cleveland Heights, Cuyahoga County, Ohio)
Required, and required everywhere in Ohio rather than in a mapped zone. Residential Code of Ohio section 905.1.2 conditions the ice barrier on a local history of ice damming "as designated in Table 301.2(1)", and the state's own Table 301.2(1) answers that designation for the whole state: the ICE BARRIER UNDERLAYMENT REQUIRED column reads "Yes", and note h to the table states that "all jurisdictions in Ohio have a history of local damage from the effects of ice damming." So there is no per city determination to look up. The assembly is specified in 905.1.2: the barrier "shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet shall be used in place of normal underlayment and extend from the lowest edges of all roof surfaces to a point not less than 24 inches (610 mm) inside the exterior wall line of the building." That 24 inches is measured along the slope from where the projected outside face of the wall meets the roof deck. On roofs of 8:12 or steeper the barrier "shall also be applied not less than 36 inches (914 mm) measured along the roof slope from the eave edge of the building." It applies to asphalt shingles, metal roof shingles, mineral surfaced roll roofing, slate and slate-type shingles, wood shingles and wood shakes. One exception travels with it: "Detached accessory structures and roof assemblies terminating at a vertical wall over unconditioned floor areas."
City of Cleveland, Ohio - Department of Building and Housing (City of Cleveland, Ohio)
SET BY STATE RULE -- applies identically in Cleveland as everywhere else in Ohio. RCO Table 301.2(1) (OAC 4101:8-3-01, effective 7/1/2019) pre-fills "Ice Barrier Underlayment Required" as "Yes" for the whole state, with footnote (h): "In accordance with Sections 905.1.2, 905.4.3.1, 905.5.3.1, 905.6.3.1, 905.7.3.1 and 905.8.3.1, all jurisdictions in Ohio have a history of local damage from the effects of ice damming." Ohio therefore invokes the IRC ice-damming trigger uniformly by rule rather than leaving it to local determination. RCO Section 905.1.2 (OAC 4101:8-9-01, effective 7/1/2019) reads verbatim: "In areas where there has been a history of ice forming along the eaves causing a backup of water as designated in Table 301.2(1), an ice barrier shall be installed for asphalt shingles, metal roof shingles, mineral-surfaced roll roofing, slate and slate-type shingles, wood shingles and wood shakes. The ice barrier shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet shall be used in place of normal underlayment and extend from the lowest edges of all roof surfaces to a point not less than 24 inches (610 mm) inside the exterior wall line of the building. The 24 inch measurement shall be along the slope of the roof from the point where the projected outside face of the wall intersects the roof deck. On roofs with slope equal to or greater than eight units vertical in 12 units horizontal (67-percent slope), the ice barrier shall also be applied not less than 36 inches measured along the roof slope from the eave edge of the building." The last two sentences are Ohio-specific additions beyond base 2018 IRC text. Exception, verbatim: "Detached accessory structures and roof assemblies terminating at a vertical wall over unconditioned floor areas."
City of Columbus, Ohio - Department of Building and Zoning Services (City of Columbus, Ohio)
SET BY STATE RULE -- applies identically in Columbus as everywhere else in Ohio. RCO Table 301.2(1) as printed in OAC 4101:8-3-01 pre-fills "Ice Barrier Underlayment Required" as "Yes" for the whole state rather than leaving it to local determination, and its footnote (h) explains why: "In accordance with Sections 905.1.2, 905.4.3.1, 905.5.3.1, 905.6.3.1, 905.7.3.1 and 905.8.3.1, all jurisdictions in Ohio have a history of local damage from the effects of ice damming." RCO Section 905.1.2 (OAC 4101:8-9-01) then requires: "an ice barrier shall be installed for asphalt shingles, metal roof shingles, mineral-surfaced roll roofing, slate and slate-type shingles, wood shingles and wood shakes. The ice barrier shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet shall be used in place of normal underlayment and extend from the lowest edges of all roof surfaces to a point not less than 24 inches (610 mm) inside the exterior wall line of the building." Ohio adds text beyond the base 2018 IRC: "The 24 inch measurement shall be along the slope of the roof from the point where the projected outside face of the wall intersects the roof deck. On roofs with slope equal to or greater than eight units vertical in 12 units horizontal (67-percent slope), the ice barrier shall also be applied not less than 36 inches measured along the roof slope from the eave edge of the building." Exception: "Detached accessory structures and roof assemblies terminating at a vertical wall over unconditioned floor areas" (the italicized portion is also an Ohio-specific addition).
City of Dayton, Ohio - Division of Building Inspection (City of Dayton, Ohio)
SET BY STATE RULE - required in Dayton exactly as everywhere else in Ohio, because Ohio makes the ice-damming determination statewide by rule rather than leaving it to local option. RCO Table 301.2(1) pre-fills "Ice Barrier Underlayment Required" as "Yes" for the whole state, with footnote (h) reciting that "all jurisdictions in Ohio have a history of local damage from the effects of ice damming." RCO Section 905.1.2 (Ice barriers) then requires an ice barrier for asphalt shingles and other listed coverings, consisting of not fewer than two layers of cemented underlayment or a self-adhering polymer-modified bitumen sheet, extending not less than 24 inches inside the exterior wall line (36 inches on slopes of 8:12 or greater). Exception: "Detached accessory structures and roof assemblies terminating at a vertical wall over unconditioned floor areas."
City of Elyria, Ohio - Building Department (City of Elyria, Ohio)
SET BY STATE RULE, confirmed from the state's own copies of both RCO instruments, each read in full. RCO Table 301.2(1) ("Climatic and Geographic Design Criteria," OAC 4101:8-3-01, effective 7/1/2019) pre-fills "Ice Barrier Underlayment Required" as "Yes" for the entire state, with footnote (h) reciting, verbatim: "In accordance with Sections 905.1.2, 905.4.3.1, 905.5.3.1, 905.6.3.1, 905.7.3.1 and 905.8.3.1, all jurisdictions in Ohio have a history of local damage from the effects of ice damming." RCO Section 905.1.2 (OAC 4101:8-9-01) requires the ice barrier to extend from the lowest roof edge to a point not less than 24 inches inside the exterior wall line (36 inches on slopes at or above 8:12), consisting of not fewer than two layers of cemented underlayment or a self-adhering polymer-modified bitumen sheet. No Elyria-specific ice-barrier statement was found in the city's own permit materials, and Elyria's full codified ordinances are not accessible online (see the note under adopted_code).
City of Euclid, Ohio - Department of Building and Housing (City of Euclid, Cuyahoga County, Ohio)
Required, and required across the whole state rather than in a mapped zone, which matters on a Lake Erie shoreline city. Residential Code of Ohio section 905.1.2 conditions the ice barrier on a local history of ice damming "as designated in Table 301.2(1)", and Ohio's own Table 301.2(1) makes that designation statewide: the ICE BARRIER UNDERLAYMENT REQUIRED column reads "Yes", and note h to the table states that "all jurisdictions in Ohio have a history of local damage from the effects of ice damming." There is therefore no per-city determination to look up. The barrier "shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet shall be used in place of normal underlayment and extend from the lowest edges of all roof surfaces to a point not less than 24 inches (610 mm) inside the exterior wall line of the building," measured along the slope from where the projected outside face of the wall meets the deck. On roofs of 8:12 or steeper it "shall also be applied not less than 36 inches (914 mm) measured along the roof slope from the eave edge." One exception travels with it: "Detached accessory structures and roof assemblies terminating at a vertical wall over unconditioned floor areas." It applies to asphalt shingles, metal roof shingles, mineral surfaced roll roofing, slate and slate-type shingles, wood shingles and wood shakes.
City of Hamilton, Ohio - Building Department (City of Hamilton, Ohio)
CITY-CONFIRMED, and consistent with the statewide RCO floor. The City of Hamilton's own "Roofing Permit (Existing Building)" application states, verbatim: "NOTICE: ALL ROOFING PERMITS REQUIRE INSPECTION APPROVAL! INSPECTION IS REQUIRED TO VERIFY THE ICE GUARD AND UNDERLAYMENT INSTALLATION AS WELL AS THE ROOF COMPLETION." The form does not itself state a coverage distance. Ohio's statewide floor (RCO Table 301.2(1), OAC 4101:8-3-01, effective 7/1/2019) pre-fills "Ice Barrier Underlayment Required" as "Yes" for the entire state, with RCO Section 905.1.2 (OAC 4101:8-9-01) requiring the ice barrier to extend from the lowest roof edge to a point not less than 24 inches inside the exterior wall line (36 inches on slopes at or above 8:12).
City of Kettering, Ohio - Building Division (City of Kettering, Ohio)
SET BY STATE RULE. RCO Table 301.2(1) (OAC 4101:8-3-01, effective 7/1/2019) pre-fills "Ice Barrier Underlayment Required" as "Yes" for the entire state, with footnote (h) reciting, verbatim, that per Sections 905.1.2, 905.4.3.1, 905.5.3.1, 905.6.3.1, 905.7.3.1 and 905.8.3.1, "all jurisdictions in Ohio have a history of local damage from the effects of ice damming." RCO Section 905.1.2 requires the ice barrier for asphalt shingles (among other coverings) to consist of "not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet," extending from the lowest roof edge to a point not less than 24 inches inside the exterior wall line (36 inches on slopes at or above 8:12). Codified Ordinances Chapter 1301 (Kettering Building Codes) does not separately address ice barriers and amends nothing in RCO Chapter 9.
City of Lorain, Ohio - Building, Housing and Planning Department (City of Lorain, Ohio)
SET BY STATE RULE. RCO Section 905.1.2 (OAC 4101:8-9-01, effective 7/1/2019), confirmed from the state's own copy, requires an ice barrier for asphalt shingles (among other roof coverings) "in areas where there has been a history of ice forming along the eaves causing a backup of water as designated in Table 301.2(1)," consisting of not fewer than two layers of cemented underlayment or a self-adhering polymer-modified bitumen sheet, extending from the lowest roof edge to a point not less than 24 inches inside the exterior wall line (36 inches on slopes at or above 8:12). RCO Table 301.2(1) (OAC 4101:8-3-01, effective 7/1/2019) also pre-fills "Ice Barrier Underlayment Required" as "Yes" statewide, with footnote (h) reciting that, per Sections 905.1.2, 905.4.3.1, 905.5.3.1, 905.6.3.1, 905.7.3.1 and 905.8.3.1, "all jurisdictions in Ohio have a history of local damage from the effects of ice damming." Lorain's own permit materials do not separately restate this requirement, but it applies to Lorain as the statewide floor.
City of Mansfield, Ohio - Bureau of Building Inspections, Licenses and Permits (City of Mansfield, Richland County, Ohio)
Required, and required across the whole state rather than in a mapped zone. Residential Code of Ohio section 905.1.2 conditions the ice barrier on a local history of ice damming "as designated in Table 301.2(1)", and Ohio's own Table 301.2(1) makes that designation statewide: the ICE BARRIER UNDERLAYMENT REQUIRED column reads "Yes", and note h to the table states that "all jurisdictions in Ohio have a history of local damage from the effects of ice damming." There is therefore no per-city determination to look up. The barrier "shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet shall be used in place of normal underlayment and extend from the lowest edges of all roof surfaces to a point not less than 24 inches (610 mm) inside the exterior wall line of the building," measured along the slope from where the projected outside face of the wall meets the deck. On roofs of 8:12 or steeper it "shall also be applied not less than 36 inches (914 mm) measured along the roof slope from the eave edge." One exception travels with it: "Detached accessory structures and roof assemblies terminating at a vertical wall over unconditioned floor areas." It applies to asphalt shingles, metal roof shingles, mineral surfaced roll roofing, slate and slate-type shingles, wood shingles and wood shakes.
City of Mentor, Ohio - Engineering and Building Department (City of Mentor, Lake County, Ohio)
Required, and required across the whole state rather than in a mapped zone, which matters on a Lake Erie snowbelt site. Residential Code of Ohio section 905.1.2 conditions the ice barrier on a local history of ice damming "as designated in Table 301.2(1)", and Ohio's own Table 301.2(1) makes that designation statewide: the ICE BARRIER UNDERLAYMENT REQUIRED column reads "Yes", and note h to the table states that "all jurisdictions in Ohio have a history of local damage from the effects of ice damming." There is therefore no per-city determination to look up. The barrier "shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet shall be used in place of normal underlayment and extend from the lowest edges of all roof surfaces to a point not less than 24 inches (610 mm) inside the exterior wall line of the building," measured along the slope from where the projected outside face of the wall meets the deck. On roofs of 8:12 or steeper it "shall also be applied not less than 36 inches (914 mm) measured along the roof slope from the eave edge." One exception travels with it: "Detached accessory structures and roof assemblies terminating at a vertical wall over unconditioned floor areas."
City of Parma, Ohio - Building Department (City of Parma, Ohio)
CITY-CONFIRMED, and independently required at the state level. Parma's own "Windows / Siding / Roofing / Door Permit Application" (Building Department form WSR08072026) requires the applicant to initial, verbatim: "Roof Ice Protection required from eave to 24 inches inside exterior wall." This matches the statewide RCO floor: RCO Table 301.2(1) (OAC 4101:8-3-01, effective 7/1/2019), confirmed from the state's own copy, pre-fills "Ice Barrier Underlayment Required" as "Yes" for the entire state, with footnote (h) reciting that, per Sections 905.1.2, 905.4.3.1, 905.5.3.1, 905.6.3.1, 905.7.3.1 and 905.8.3.1, "all jurisdictions in Ohio have a history of local damage from the effects of ice damming." RCO Section 905.1.2 requires the ice barrier to extend from the lowest roof edge to a point not less than 24 inches inside the exterior wall line (36 inches on slopes at or above 8:12), consisting of not fewer than two layers of cemented underlayment or a self-adhering polymer-modified bitumen sheet.
City of Springfield, Ohio - Building Regulations Division (City of Springfield, Ohio)
CITY-CONFIRMED, and independently required at the state level. Springfield's own Residential Re-roofing Affidavit Application (page 2, "Residential Roofing Regulations," read in full) states, verbatim: "Per Table 301.2(1) ice barrier underlayment is required in the state of Ohio." Springfield's own "Current Adopted Ohio Building Codes" document (read in full) prints a Springfield-specific Design Criteria table with "Ice Shield Underlayment Req." listed as "Yes." This matches RCO Table 301.2(1) (OAC 4101:8-3-01, effective 7/1/2019, read in full), which pre-fills "Ice Barrier Underlayment Required" as "Yes" statewide, with RCO Section 905.1.2 requiring the ice barrier to extend from the lowest roof edge to a point not less than 24 inches inside the exterior wall line (36 inches on slopes at or above 8:12).
City of Strongsville, Ohio - Building Department (City of Strongsville, Cuyahoga County, Ohio)
Required, and required across the whole state rather than in a mapped zone. Residential Code of Ohio section 905.1.2 conditions the ice barrier on a local history of ice damming "as designated in Table 301.2(1)", and Ohio's own Table 301.2(1) makes that designation statewide: the ICE BARRIER UNDERLAYMENT REQUIRED column reads "Yes", and note h to the table states that "all jurisdictions in Ohio have a history of local damage from the effects of ice damming." There is therefore no per-city determination to look up. The barrier "shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet shall be used in place of normal underlayment and extend from the lowest edges of all roof surfaces to a point not less than 24 inches (610 mm) inside the exterior wall line of the building," measured along the slope from where the projected outside face of the wall meets the deck. On roofs of 8:12 or steeper it "shall also be applied not less than 36 inches (914 mm) measured along the roof slope from the eave edge." One exception travels with it: "Detached accessory structures and roof assemblies terminating at a vertical wall over unconditioned floor areas." It applies to asphalt shingles, metal roof shingles, mineral surfaced roll roofing, slate and slate-type shingles, wood shingles and wood shakes.
City of Toledo, Ohio - Division of Building Inspection (City of Toledo, Ohio)
SET BY STATE RULE -- required in Toledo exactly as everywhere else in Ohio, because Ohio makes the ice-damming determination statewide by rule rather than leaving it to local option. RCO Table 301.2(1) pre-fills "Ice Barrier Underlayment Required" as "Yes" for the whole state, with footnote (h): "In accordance with Sections 905.1.2, 905.4.3.1, 905.5.3.1, 905.6.3.1, 905.7.3.1 and 905.8.3.1, all jurisdictions in Ohio have a history of local damage from the effects of ice damming." RCO Section 905.1.2 (Ice barriers) provides, verbatim: "In areas where there has been a history of ice forming along the eaves causing a backup of water as designated in Table 301.2(1), an ice barrier shall be installed for asphalt shingles, metal roof shingles, mineral-surfaced roll roofing, slate and slate-type shingles, wood shingles and wood shakes. The ice barrier shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet shall be used in place of normal underlayment and extend from the lowest edges of all roof surfaces to a point not less than 24 inches (610 mm) inside the exterior wall line of the building. The 24 inch measurement shall be along the slope of the roof from the point where the projected outside face of the wall intersects the roof deck. On roofs with slope equal to or greater than eight units vertical in 12 units horizontal (67-percent slope), the ice barrier shall also be applied not less than 36 inches measured along the roof slope from the eave edge of the building." Exception, verbatim: "Detached accessory structures and roof assemblies terminating at a vertical wall over unconditioned floor areas." Toledo's own (stale, pre-2019-RCO) Construction Procedures handout independently prints a Toledo-specific reading of the same table row confirming "Ice Shield Underlayment Required: Yes" for Toledo/Lucas County, consistent with the statewide rule.
Hamilton County, Ohio - Buildings and Inspections (Hamilton County, Ohio)
COUNTY-CONFIRMED, and independently required at the state level. Hamilton County's own Roofing Data Sheet, Note 3, states verbatim: "Ice barriers are required from the lowest edges of all roof surfaces upward to a point not less than 24-inches (measured horizontally) inside the front face of the exterior building wall." This matches the statewide RCO floor: RCO Table 301.2(1) (OAC 4101:8-3-01, effective 7/1/2019) pre-fills "Ice Barrier Underlayment Required" as "Yes" statewide, and RCO Section 905.1.2 requires the ice barrier to extend from the lowest roof edge to a point not less than 24 inches inside the exterior wall line (36 inches on slopes at or above 8:12).
Lucas County, Ohio - Building Regulations Department (Lucas County, Ohio)
Required, and required across the whole state rather than in a mapped zone. Residential Code of Ohio section 905.1.2 conditions the ice barrier on a local history of ice damming "as designated in Table 301.2(1)", and Ohio's own Table 301.2(1) makes that designation statewide: the ICE BARRIER UNDERLAYMENT REQUIRED column reads "Yes", and note h to the table states that "all jurisdictions in Ohio have a history of local damage from the effects of ice damming." There is therefore no per-city determination to look up. The barrier "shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet shall be used in place of normal underlayment and extend from the lowest edges of all roof surfaces to a point not less than 24 inches (610 mm) inside the exterior wall line of the building," measured along the slope from where the projected outside face of the wall meets the deck. On roofs of 8:12 or steeper it "shall also be applied not less than 36 inches (914 mm) measured along the roof slope from the eave edge." One exception travels with it: "Detached accessory structures and roof assemblies terminating at a vertical wall over unconditioned floor areas." It applies to asphalt shingles, metal roof shingles, mineral surfaced roll roofing, slate and slate-type shingles, wood shingles and wood shakes.
Summit County, Ohio - Division of Building Standards (Summit County, Ohio)
SET BY STATE RULE. RCO Table 301.2(1) (OAC 4101:8-3-01, effective 7/1/2019), read in full from the state's own copy, pre-fills "Ice Barrier Underlayment Required" as "Yes" for the entire state, with footnote (h) reciting, verbatim, that per Sections 905.1.2, 905.4.3.1, 905.5.3.1, 905.6.3.1, 905.7.3.1 and 905.8.3.1, "all jurisdictions in Ohio have a history of local damage from the effects of ice damming." RCO Section 905.1.2 requires the ice barrier to extend from the lowest roof edge to a point not less than 24 inches inside the exterior wall line (36 inches on slopes at or above 8:12), consisting of not fewer than two layers of cemented underlayment or a self-adhering polymer-modified bitumen sheet. No Summit-County-specific confirmation or expansion of this requirement was found; the county's own codified Building Code could not be opened (see adopted_code).
Ice barrier required — Oklahoma (11)
City of Broken Arrow - Community Permitting and Licensing Division (City of Broken Arrow, Oklahoma)
A 36-inch-wide ice barrier IS required in all valleys ("installed in all valleys, run the length of the valley, and centered on the valley") and at all changes in roof pitch where the lower roof has a lower pitch than the upper roof -- unconditional requirements added to IRC Sec. 905.1.2 by the OUBCC 2018 IRC Permanent Rule, "the statewide minimum code for residential building construction... pursuant to 59 O.S. Sec. 1000.23," which "may only be amended or altered by other jurisdictions pursuant to Oklahoma law"; the city's own amendment ordinance, read in full, does not alter Sec. 905.1.2. At the EAVES, the city's own amended Table R301.2(1) answers the eave ice-damming trigger "Ice Barrier Underlayment Required = No" (Sec. 6-37(g), Ord. No. 3826, 4-16-2024). Net effect: ice barrier required in valleys and at pitch changes everywhere in the city; not required at eaves.
City of Edmond Department of Building & Safety (City of Edmond, Oklahoma)
"Ice and water shield is currently only required at valleys and at roof pitch changes where the lower pitch is less than the upper pitch." (City of Edmond Department of Building & Safety roofing FAQ). Not required roof-wide -- only at valleys and pitch changes.
City of Jenks - Building Inspections Department (City of Jenks, Oklahoma)
A 36-inch-wide ice barrier IS required in all valleys ("installed in all valleys, run the length of the valley, and centered on the valley") and at all changes in roof pitch where the lower roof has a lower pitch than the upper roof -- unconditional requirements added to IRC Sec. 905.1.2 by the OUBCC 2018 IRC Permanent Rule, "the statewide minimum code for residential building construction... pursuant to 59 O.S. Sec. 1000.23." Jenks Sec. 4-1-1 through 4-1-8 contains no local amendment touching Sec. 905.1.2 or any other roofing provision, and no local climate-design table addressing the eave ice-damming trigger was found, so only the unconditional valley and pitch-change requirement is stated here.
City of Midwest City - Permits & Building Inspections Division (City of Midwest City, Oklahoma)
A 36-inch-wide ice barrier IS required in all valleys ("installed in all valleys, run the length of the valley, and centered on the valley") and at all changes in roof pitch where the lower roof has a lower pitch than the upper roof -- unconditional requirements added to IRC Sec. 905.1.2 by the OUBCC 2018 IRC Permanent Rule, "the statewide minimum code for residential building construction... pursuant to 59 O.S. Sec. 1000.23," which "may only be amended or altered by other jurisdictions pursuant to Oklahoma law." Midwest City Code of Ordinances Sec. 9-5(b) adopts the 2018 International Residential Code, and Sec. 9-7 ("Code amended--International Residential Code") (Ord. No. 3560, Sec. 1, 4-23-24; Ord. No. 3590, Sec. 1, 3-25-25; Ord. No. 3591, Sec. 2, 3-25-25), read in full, amends only administrative/permit provisions (102.4.1, 104.1, 104.2, 105.10, 107.3.1, 108.2, 109.4, 110.0, 112.1) -- it does not alter Sec. 905.1.2, so the statewide amendment stands as the city's operative law. No local Table R301.2(1) exists for Midwest City, so the eave/ice-damming trigger cannot be stated here -- only the unconditional valley and pitch-change requirement is published.
City of Moore - Building Permits & Inspections (Community Development Department) (City of Moore, Oklahoma)
Required -- and, unusually among Oklahoma jurisdictions, set by the City of Moore's OWN local amendments rather than by the state minimum. Moore's own amended IRC Table R301.2(1) (Municipal Code Sec. 5-204, table amendment codified as an image reproduction of Ord. No. 1039.23, 12-18-2023) answers the "Ice Barrier Underlayment Required" cell "Yes" (alongside: ground snow load 10 lb/ft2, wind design speed 135 mph, topographic/special-wind-region/windborne-debris all "No," seismic design category C, winter design temp 13 F, air freezing index 300, mean annual temp 60.9 F). Separately and more specifically, Moore's Sec. 5-204 directly rewrites IRC R905.1.2 itself (not merely silence/adopt-unamended): "R905.1.2 Ice barriers. In the roof valleys an ice barrier shall be installed for asphalt shingles, metal roof shingles, mineral surface roll roofing, s[l]ate and slate-type shingles, wood shingles and wood shakes. The ice barrier shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering polymer modified bitumen sheet shall be used in place of normal underlayment and extend from the lowest edge of the roof surface. Exception: Detached accessory structures not containing conditioned floor area." That local text sets the valley trigger and specifies the underlayment method (two cemented layers, or a self-adhering membrane) but does not separately restate a roof-pitch-change trigger. Oklahoma's OUBCC 2018 IRC Permanent Rule -- the statewide minimum code Moore's Sec. 5-201/5-204 explicitly adopts "as amended and modified by the Oklahoma uniform building code commission pursuant to 59 O.S. Sec. 1000.23" -- additionally and unconditionally requires a 36-inch-wide ice barrier "at all change in roof pitch in which the lower roof has a lower pitch than the upper roof," a trigger Moore's own local amendment neither restates nor contradicts. Net effect in Moore: ice barrier required at eaves (per the city's own Table R301.2(1) "Yes"), in all roof valleys (per the city's own R905.1.2 text and method), and at pitch changes (per the state minimum, which Moore's own amendment does not address).
City of Mustang - Community Development Department (City of Mustang, Oklahoma)
A 36-inch-wide ice barrier IS required in all valleys ("installed in all valleys, run the length of the valley, and centered on the valley") and at all changes in roof pitch where the lower roof has a lower pitch than the upper roof -- unconditional requirements added to IRC Sec. 905.1.2 by the OUBCC 2018 IRC Permanent Rule, "the statewide minimum code for residential building construction... pursuant to 59 O.S. Sec. 1000.23," which "may only be amended or altered by other jurisdictions pursuant to Oklahoma law"; the city's own amendment ordinance, read in full, does not alter Sec. 905.1.2. At the EAVES, the city's own Ordinance No. 1269 (Sec. 18-33.B item 18, 8-2-2022) fills the same table cell "ice barrier underlayment required - no". Net effect: ice barrier required in valleys and at pitch changes everywhere in the city; not required at eaves.
City of Norman Development Services Division (City of Norman, Oklahoma)
"Does the code obligate Ice Barrier Underlayment? In most areas NO. But by state amendment a 36" wide strip is required to be installed in valleys and at roof pitch changes. (R905.1.2 with OUBCC Amendment)" (City of Norman "Common Questions for Roofing with Asphalt Shingles," Development Services Division / Building Permits and Inspections). Not required roof-wide -- only at valleys and roof pitch changes.
City of Oklahoma City - Development Services Department (City of Oklahoma City, Oklahoma)
A 36-inch-wide ice barrier IS required in all valleys ("installed in all valleys, run the length of the valley, and centered on the valley") and at all changes in roof pitch where the lower roof has a lower pitch than the upper roof -- unconditional requirements added to IRC Sec. 905.1.2 by the OUBCC 2018 IRC Permanent Rule, "the statewide minimum code for residential building construction... pursuant to 59 O.S. Sec. 1000.23," which "may only be amended or altered by other jurisdictions pursuant to Oklahoma law." At the EAVES, the City's own Re-Roofing Permit Requirements checklist answers the eave ice-damming trigger directly: "Q7. Are ice barriers required? No." (effective 7/28/25), consistent with the City's own Table R301.2(1), which fills "Ice Barrier Underlayment Required - No." Net effect: ice barrier required in valleys and at pitch changes everywhere in the city; not required at eaves. The same Sec. 905.1.2 text appears word-for-word in the City's own "2018 IRC Amendments, State Amendments Included" document.
City of Tulsa Development Services Department - Permit Center (City of Tulsa, Oklahoma)
Tulsa Code of Ordinances Title 51, Chapter 2, Section 201, Section 905.1.2 Ice barriers (locally amended): base trigger is "In areas where there has been a history of ice forming along the eaves causing a backup of water as designated in Table R301.2(1), an ice barrier shall be installed for asphalt shingles ... extend from the lowest edges of all roof surfaces to a point not less than 24 inches (610 mm) inside the exterior wall line of the building," plus two Tulsa-added unconditional triggers: "(B) A 36-inch wide (914 mm) ice barrier shall be installed in all valleys, run the length of the valley, and centered on the valley," and "(C) A 36-inch wide (914 mm) ice barrier shall be installed at all change in roof pitch in which the lower roof has a lower pitch than the upper roof. The ice barrier is run the length of the change in pitch and cemented on the change in pitch."
City of Yukon - Development Services (City of Yukon, Oklahoma)
City of Yukon Ordinance No. 1414 (adopted Aug. 18, 2020), Sec. 204-138, amends the adopted 2015 International Residential Code Table R301.2(1) "Climatic and Geographic Design Criteria" for the City of Yukon to read "Ice barrier underlayment required - Yes," alongside the table's Ground Snow Load, Wind Speed, and other city-specific design criteria entries.
Oklahoma County Planning Commission (Oklahoma County, Oklahoma)
A 36-inch-wide ice barrier IS required in all valleys ("installed in all valleys, run the length of the valley, and centered on the valley") and at all changes in roof pitch where the lower roof has a lower pitch than the upper roof -- unconditional requirements added to IRC Sec. 905.1.2 by the OUBCC 2018 IRC Permanent Rule, "the statewide minimum code for residential building construction... pursuant to 59 O.S. Sec. 1000.23." Resolution No. 2024-5421 (eff. 1-1-2025), which adopts the 2018 IRC "as modified by the OUBCC with the 2022 Oklahoma Amendments" for unincorporated Oklahoma County, read in full, does not touch any Chapter 9 Roof Assemblies provision, including Sec. 905.1.2. No local climate-design table stating whether an ice barrier is required at the EAVES was found for unincorporated Oklahoma County, so the eave question is left open here; only the unconditional valley and pitch-change requirement is stated.
Ice barrier required — Other (11)
Butler County, Ohio - Department of Development, Building and Zoning (Unincorporated Butler County, Ohio. The County's Building and Zoning staff is responsible for enforcing the building code, electrical code and zoning regulations "for the unincorporated areas of Butler County," so work inside an incorporated city or village is not this authority's. Its own inspection schedule names the townships it serves: Hanover, Morgan, Reily and Ross; College Corner, Madison, Milford, Oxford, St. Clair and Wayne; and Fairfield, Lemon, Liberty, Trenton and West Chester, which get inspections every day rather than on set days.)
Required, and required across the whole state rather than in a mapped zone. Residential Code of Ohio section 905.1.2 conditions the ice barrier on a local history of ice damming "as designated in Table 301.2(1)", and Ohio's own Table 301.2(1) makes that designation statewide: the ICE BARRIER UNDERLAYMENT REQUIRED column reads "Yes", and note h to the table states that "all jurisdictions in Ohio have a history of local damage from the effects of ice damming." There is therefore no per-city determination to look up. The barrier "shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet shall be used in place of normal underlayment and extend from the lowest edges of all roof surfaces to a point not less than 24 inches (610 mm) inside the exterior wall line of the building," measured along the slope from where the projected outside face of the wall meets the deck. On roofs of 8:12 or steeper it "shall also be applied not less than 36 inches (914 mm) measured along the roof slope from the eave edge." One exception travels with it: "Detached accessory structures and roof assemblies terminating at a vertical wall over unconditioned floor areas." It applies to asphalt shingles, metal roof shingles, mineral surfaced roll roofing, slate and slate-type shingles, wood shingles and wood shakes.
City of Dublin, Ohio - Division of Building Standards (City of Dublin, Ohio. Dublin straddles three counties — Franklin, Delaware and Union — which matters for tax but not for code, since the Residential Code of Ohio is a statewide rule.)
Required, and required across the whole state rather than in a mapped zone. Residential Code of Ohio section 905.1.2 conditions the ice barrier on a local history of ice damming "as designated in Table 301.2(1)", and Ohio's own Table 301.2(1) makes that designation statewide: the ICE BARRIER UNDERLAYMENT REQUIRED column reads "Yes", and note h to the table states that "all jurisdictions in Ohio have a history of local damage from the effects of ice damming." There is therefore no per-city determination to look up. The barrier "shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet shall be used in place of normal underlayment and extend from the lowest edges of all roof surfaces to a point not less than 24 inches (610 mm) inside the exterior wall line of the building," measured along the slope from where the projected outside face of the wall meets the deck. On roofs of 8:12 or steeper it "shall also be applied not less than 36 inches (914 mm) measured along the roof slope from the eave edge." One exception travels with it: "Detached accessory structures and roof assemblies terminating at a vertical wall over unconditioned floor areas." It applies to asphalt shingles, metal roof shingles, mineral surfaced roll roofing, slate and slate-type shingles, wood shingles and wood shakes.
City of Middletown, Ohio - Building Inspection Division (City of Middletown, Ohio. Middletown straddles Butler and Warren counties, which matters for sales tax — the two counties are at different rates and one of them changes on 2026-10-01 — but not for code, since the Residential Code of Ohio is a statewide rule.)
Required, and required across the whole state rather than in a mapped zone. Residential Code of Ohio section 905.1.2 conditions the ice barrier on a local history of ice damming "as designated in Table 301.2(1)", and Ohio's own Table 301.2(1) makes that designation statewide: the ICE BARRIER UNDERLAYMENT REQUIRED column reads "Yes", and note h to the table states that "all jurisdictions in Ohio have a history of local damage from the effects of ice damming." There is therefore no per-city determination to look up. The barrier "shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet shall be used in place of normal underlayment and extend from the lowest edges of all roof surfaces to a point not less than 24 inches (610 mm) inside the exterior wall line of the building," measured along the slope from where the projected outside face of the wall meets the deck. On roofs of 8:12 or steeper it "shall also be applied not less than 36 inches (914 mm) measured along the roof slope from the eave edge." One exception travels with it: "Detached accessory structures and roof assemblies terminating at a vertical wall over unconditioned floor areas." It applies to asphalt shingles, metal roof shingles, mineral surfaced roll roofing, slate and slate-type shingles, wood shingles and wood shakes.
City of Spearfish, South Dakota - Building Services Division (City of Spearfish, Lawrence County, South Dakota, together with the Lawrence County Joint Powers Area outside the city limits for which the City's Building Services Division issues building permits. Where an address sits relative to the city limit still matters for tax even though it does not change which desk issues the permit: the municipal sales and use tax applies inside the city and not in the surrounding unincorporated county.)
Required, and stated twice in first-party sources that agree exactly. The Climatic and Geographic Design Criteria table published inside Section 150.016(A) of the codified ordinance, headed "Climatic and Geographic Design Criteria / City of Spearfish, SD," carries the row "Ice shield under-underlayment required Yes" - the doubled "under-" is verbatim in the City's own codified text and is reproduced here rather than tidied. The City's separate Design Criteria and Adopted Codes web page states the same row as "Ice Shield Underlayment Required - Yes." The adopted 2021 International Residential Code conditions its ice barrier requirement on the designation made in Table R301.2, and Spearfish has made that designation in the affirmative, so Section R905.1.2 applies: an ice barrier of at least two layers of underlayment cemented together, or a self-adhering polymer modified bitumen sheet, extending from the eave edge to a point at least 24 inches inside the exterior wall line of the building. The requirement attaches to the work and not to the permit, so it applies to a reroof that is exempt from permit under Section 150.016(A)(1)(k) exactly as it applies to permitted work.
City of Tea, South Dakota - Planning, Zoning and Building Services (City of Tea, Lincoln County, South Dakota. Tea sits directly south of Sioux Falls and its city limits are the boundary that matters for both permitting and municipal tax, since the surrounding unincorporated Lincoln County land carries neither the City's permit requirement nor its municipal sales tax.)
Required, and stated twice by the City. Ordinance No. 299's Table R301.2, Climatic and Geographic Design Criteria, carries the entry "ICE BARRIER UNDERLAYMENT REQUIRED - Yes." The City's Asphalt Shingles Information handout gives the operative detail: "An ice barrier that consists of a least two layers of underlayment cemented together, or of a self-adhering polymer modified bitumen sheet, shall be used in lieu of normal underlayment, and extend from the eave's edge to a point at least 24 inches inside the exterior wall line of the building. The exception to this would be detached unheated structures." The transcription "a least" is the City's own and is reproduced rather than tidied. Note the exception on the face of that sentence: detached unheated structures. It is narrower than a blanket detached-garage exemption, since a heated detached garage is not within it, so confirm that specific case with the building official rather than assuming.
City of Vermillion, South Dakota - Code Enforcement Department (City of Vermillion, Clay County, South Dakota. The city limit is the boundary that matters for both the permit requirement and the municipal sales and use tax; the surrounding unincorporated Clay County land carries neither.)
Required. Section 150.03(B)(28) is Vermillion's own completed version of Table R301.2(1), Climatic and Geographic Design Criteria, and it carries the entry "Ice Barrier Underlayment Requirement yes." The adopted 2018 International Residential Code conditions its ice barrier requirement on the designation made in that table, and Vermillion has made the designation in the affirmative, so Section R905.1.2 applies: an ice barrier of at least two layers of underlayment cemented together, or a self-adhering polymer modified bitumen sheet, extending from the eave edge to a point at least 24 inches inside the exterior wall line of the building. Vermillion restates nothing further about how the barrier is to be installed, so the adopted code text is the whole of the local requirement.
Franklin County, Ohio - Building Department (Franklin County, Ohio -- unincorporated areas of the county plus the ten contract townships that route zoning compliance through the county (Brown, Clinton, Franklin, Hamilton, Madison, Mifflin, Norwich, Pleasant, Sharon and Truro townships). This does not include Columbus or the county's other incorporated cities and villages, which run their own separate residential permitting (see the Columbus, OH record for that city).)
SET BY STATE RULE. RCO Table 301.2(1) (OAC 4101:8-3-01, effective 7/1/2019), read in full from the state's own copy, pre-fills "Ice Barrier Underlayment Required" as "Yes" for the entire state, with footnote (h) reciting that "all jurisdictions in Ohio have a history of local damage from the effects of ice damming." RCO Section 905.1.2 requires the ice barrier to extend from the lowest roof edge to a point not less than 24 inches inside the exterior wall line (36 inches on slopes at or above 8:12), consisting of not fewer than two layers of cemented underlayment or a self-adhering polymer-modified bitumen sheet. No Franklin-County-specific roofing-permit form addressing ice barrier was found (unlike Parma's own form, which separately confirms the same requirement).
Montgomery County, Ohio - Building Regulations Division (Montgomery County, Ohio. The County states its own reach as "the citizens and users of buildings in many of the jurisdictions in Montgomery County, including all of the townships and several of the cities and villages." That is deliberately not a list, and this record does not turn it into one: all townships are covered, but which cities and villages are covered is not published here, so confirm the specific address with the Division before bidding.)
Required, and required across the whole state rather than in a mapped zone. Residential Code of Ohio section 905.1.2 conditions the ice barrier on a local history of ice damming "as designated in Table 301.2(1)", and Ohio's own Table 301.2(1) makes that designation statewide: the ICE BARRIER UNDERLAYMENT REQUIRED column reads "Yes", and note h to the table states that "all jurisdictions in Ohio have a history of local damage from the effects of ice damming." There is therefore no per-city determination to look up. The barrier "shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet shall be used in place of normal underlayment and extend from the lowest edges of all roof surfaces to a point not less than 24 inches (610 mm) inside the exterior wall line of the building," measured along the slope from where the projected outside face of the wall meets the deck. On roofs of 8:12 or steeper it "shall also be applied not less than 36 inches (914 mm) measured along the roof slope from the eave edge." One exception travels with it: "Detached accessory structures and roof assemblies terminating at a vertical wall over unconditioned floor areas." It applies to asphalt shingles, metal roof shingles, mineral surfaced roll roofing, slate and slate-type shingles, wood shingles and wood shakes.
Olmsted County, Minnesota - Planning Department, Inspections Division (Building code administration for four cities - Byron, Chatfield, Eyota and Stewartville - and three townships - Eyota, Marion and Quincy - within Olmsted County, Minnesota. This is not a county-wide authority and not an unincorporated-area authority. Olmsted County contains eight cities and eighteen townships; the County Planning Department's Inspections Division administers the Minnesota State Building Code for only the seven jurisdictions named above. Rochester is NOT among them - the County directs building and permitting questions inside Rochester city limits to the Rochester Building Safety department at 507-328-2600. The County states the scope itself: "The Olmsted County Planning department Inspections Division provides building code and permit administration for the cities of Byron, Chatfield, Eyota, and Stewartville as well as the townships of Eyota, Marion, and Quincy." Three other County boundaries deliberately differ and must not be conflated with this one: the Inspections Division administers the Septic System Ordinance for the townships of Eyota, Marion, Oronoco and Quincy "and for all of the small cities within Olmsted County," it administers the Water Well Ordinance "for the entire county," and it is the planning and zoning authority for only Eyota, Marion and Quincy Townships. One inconsistency is published on the County's own fees page and is reported rather than resolved: the building-permit section names the unincorporated areas of Marion, Quincy and Eyota Townships, while the manufactured-home, trade and septic sections on the same page each name Marion, Oronoco, Quincy and Eyota. Whether Oronoco Township is inside the building-permit jurisdiction is therefore stated both ways by the County. Because the County publishes an address-level Jurisdiction Checker, confirm a specific parcel there before assuming which desk holds a job.)
STATE-GOVERNED, NOT COUNTY-SET - the requirement applies identically in the jurisdictions Olmsted County serves as everywhere else in Minnesota. Minnesota Rules part 1309.0301, subpart 2 amends IRC Table R301.2(1) ("Climatic and Geographic Design Criteria") to pre-fill "ICE BARRIER UNDERLAYMENT REQUIRED[h] ... Yes" for the entire state. The Minnesota Department of Labor and Industry's guidance sheet, "Asphalt Shingle Roofing and the 2020 Minnesota Residential Code," describes what satisfies it: an ice barrier "may be at least two layers of underlayment cemented together or a self-adhering polymer modified bitumen sheet," extending from the eave edge to a point at least 24 inches inside the exterior wall line of the building. The County has no authority to opt out (Minn. Stat. 326B.121, subd. 1 and subd. 2(c), with "municipality" defined at Minn. Stat. 326B.103, subd. 9 to include a county). Garage and detached-accessory-structure applicability is worded differently by different Minnesota jurisdictions, so confirm that specific case with the Inspections Division rather than assuming a blanket detached-garage exemption.
Scott County, Iowa - Planning & Development Department (Unincorporated Scott County, Iowa, plus the Cities of Dixon, Donahue, LeClaire, Long Grove, McCausland, Panorama Park, Princeton, and Riverdale under a 28E intergovernmental agreement. Davenport and Bettendorf are explicitly excluded — those two cities issue their own building permits.)
Scott County's own Table R301.2 insert, added by Ordinance No. 24-07 Sec. 5-6 item F (applicable to the 2021 IRC as adopted by the same ordinance), lists "Ice Barrier Underlayment Required: Yes" as a filled-in table value for the jurisdiction.
Stark County, Ohio - Building Department (Unincorporated Stark County, Ohio, plus contracting villages. For RESIDENTIAL work the County's own jurisdiction directory covers the townships of Bethlehem, Canton, Jackson, Lake, Lawrence, Lexington, Marlboro, Nimishillen, Osnaburg, Paris, Perry, Pike, Plain, Sandy, Sugarcreek, Tuscarawas and Washington, and the villages of Brewster, East Canton, Harmon, Hills and Dales, Magnolia, Meyers Lake, Minerva and Waynesburg. Alliance, Beach City, East Sparta, Hartville, Louisville, Navarre and Wilmot are listed for COMMERCIAL work only, so residential roofing in those seven is not this authority's. Canal Fulton, Canton, Massillon and North Canton are outside the County's jurisdiction entirely and run their own building departments.)
Required, and required across the whole state rather than in a mapped zone. Residential Code of Ohio section 905.1.2 conditions the ice barrier on a local history of ice damming "as designated in Table 301.2(1)", and Ohio's own Table 301.2(1) makes that designation statewide: the ICE BARRIER UNDERLAYMENT REQUIRED column reads "Yes", and note h to the table states that "all jurisdictions in Ohio have a history of local damage from the effects of ice damming." Stark County reprints the requirement on its Residential Guidelines for Reroof form, so it is the County's published expectation and not merely a state rule. The barrier "shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet shall be used in place of normal underlayment and extend from the lowest edges of all roof surfaces to a point not less than 24 inches (610 mm) inside the exterior wall line of the building," measured along the slope from where the projected outside face of the wall meets the deck. On roofs of 8:12 or steeper it "shall also be applied not less than 36 inches (914 mm) measured along the roof slope from the eave edge." One exception travels with it and the County prints it too: "Detached accessory structures and roof assemblies terminating at a vertical wall over unconditioned floor areas." It applies to asphalt shingles, metal roof shingles, mineral surfaced roll roofing, slate and slate-type shingles, wood shingles and wood shakes.
Ice barrier required — South Dakota (11)
City of Aberdeen, South Dakota - Building Inspection Department (City of Aberdeen, South Dakota)
The City's own "Residential Shingling Guide" states: "Aberdeen, SD is designated as an area subject to ice forming along eaves and thus causing water backup. An approved ice barrier shall be installed under all types of roofing unless specified otherwise by the manufacturer." The guide separately exempts detached garages and other unconditioned, non-habitable structures from the ice-barrier requirement, and states: "Ice barriers shall extend from the lowest edge of all roof surfaces to a point not less than 24 inches inside the exterior wall line of the building. Roofs having a slope equal or greater than 8 units vertical in 12 units horizontal (8 in 12 pitch), the ice barrier shall be applied not less than 36 inches measured along the roof slope from the eave edge of the building." This matches the City's own amendment to Table R301.2(1) of the adopted 2018 IRC (Sec. 12-21(2)), which fills in "Ice barrier underlayment required" as "Yes."
City of Box Elder, South Dakota - Planning and Zoning Department (City of Box Elder, Pennington and Meade Counties, South Dakota)
AN AFFIRMATIVE LOCAL MANDATE, not an inference from a design criteria table. Box Elder amends the ice barrier twice, in the general roofing section and again in the asphalt shingle section, in identical terms. Sec. 6-257 (amending IRC R905.1.2) and Sec. 6-258 (amending IRC R905.2.7.1) both read: "Ice barrier is required. An ice barrier that consists of a least two layers of underlayment cemented together or of a self-adhering polymer modified bitumen sheet, shall be used in lieu of normal underlayment and extend from the lowest edges of all roof surfaces to a point at least 24 inches (610 mm) inside the exterior wall line of the building. Exception: Detached accessory structures that contain no conditioned floor area." ("a least" is the codification's own typographical error for "at least"; quoted as published.) Both sections derive from Ord. No. 642, 2-14-2020 and were amended by Ord. 748, 6/5/2024. The City's climatic and geographic design criteria table corroborates it, carrying "Ice Barrier Underlay Requirement: Yes." The only exception is the detached accessory structure with no conditioned floor area, so an unheated detached garage is treated differently from the house.
City of Brandon, South Dakota - Planning and Inspection Department (City of Brandon, Minnehaha County, South Dakota)
Required. Brandon fills in IRC Table R301.2(1), Climatic and Geographic Design Criteria, and its entry for "Ice barrier underlayment required" is "Yes". Because Brandon amends no section of the roofing chapter, the base code attaches to that entry unmodified: 2021 IRC R905.1.2 makes the ice barrier mandatory in jurisdictions where Table R301.2(1) so indicates, and the model footnote Brandon reproduces states the test the City was answering - "where there has been a history of local damage from the effects of ice damming, the jurisdiction shall fill in this part of the table with 'YES.' Otherwise, the jurisdiction shall fill in this part of the table with 'NO.'" Brandon answered YES. The rest of the City's filled table, from the same amendment: ground snow load 40 psf; seismic design category A; weathering severe; frost line depth 42 inches; termite slight to moderate; winter design temperature -11 degrees F; air freezing index 3,000; mean annual temperature 46 degrees F. One cell of that table was plainly adapted from a neighbouring city and has not been corrected: the flood hazards entry reads "Sioux Falls entered the regular phase of the National Flood Insurance Program on September 17, 1979," naming Sioux Falls rather than Brandon. It does not touch any roofing value, but it is a reason to confirm an unusual design figure with the Building Department on 605-582-8987 rather than reading it off the table alone.
City of Brookings, South Dakota - Community Development Department, Building Services Division (City of Brookings, South Dakota)
Ordinance No. 23-008 fills in Table R301.2 (Climatic and Geographic Design Criteria) for Brookings; line 8 of that table, as printed in the city's own ordinance, reads "Ice barrier underlayment requirement ... Yes." Under the 2021 IRC, that Table R301.2 entry is what triggers the ice-barrier-underlayment requirement, and Brookings' own adopting ordinance sets it to Yes.
City of Harrisburg, South Dakota - Building Services (City of Harrisburg, Lincoln County, South Dakota)
Required. Ordinance #2021-17 fills in the City's climatic and geographic design criteria by amendment: "Table R301.2 Climatic and Geographic Design Criteria, is hereby amended by inserting the following information into the table: ... Ice Barrier Underlayment Required: Yes;" Because Harrisburg amends no section of the roofing chapter, the base code attaches to that entry unmodified - 2021 IRC R905.1.2 makes the ice barrier mandatory in jurisdictions where Table R301.2(1) so indicates. An ice barrier under that section is at least two layers of underlayment cemented together or a self-adhering polymer modified bitumen sheet, extending from the eave edge to a point at least 24 inches inside the exterior wall line of the building. Other values inserted by the same amendment: ground snow load 40 psf; topographic effects no; special wind region no; windborne debris zone no.
City of Pierre, South Dakota - Development Services, Building Department (City of Pierre, South Dakota)
The city's Chapter 11, Article 4 amends Section R905.1.2 (Ice Barrier) directly: "In areas where there has been a history of ice forming along the eaves causing a backup of water as designated in Table R301.2(1), an ice barrier shall be installed for asphalt shingles, metal roof shingles, mineral surfaced roll roofing, slate and slate-type shingles, wood shingles and wood shakes," extending "at least 24 inches inside the exterior wall line" on roofs under 5:12 pitch and 36 inches on roofs 5:12 or steeper. The article's own Table R301.2(1) climatic and geographic design criteria table sets "Ice Barrier Underlayment Required: Yes" for Pierre.
City of Rapid City, South Dakota - Community Planning & Development Services, Building Services Division (City of Rapid City, South Dakota)
Locally amended, not left to the baseline model-code trigger. RCMC 15.13.270 is titled "IRC Chapter 9, Section R905.1.2 Ice barrier--Amended" and amends that section of the adopted 2018 IRC to read in its entirety as follows, quoted from the section read live on 2026-08-08: "R905.1.2 Ice barrier. In areas where there has been a history of ice forming along the eaves causing a backup of water as designated in Table R301.2(1), an ice barrier that consists of a least two layers of underlayment cemented together or of a self-adhering polymer modified bitumen sheet, shall be used in lieu of normal underlayment and extend from the lowest edges of all roof surfaces to a point at least 24 inches (610 mm) inside the exterior wall line of the building." (The "a least" is the code's own typographical error, reproduced here rather than silently repaired.) The amended section carries ONE exception - "Detached accessory structures that contain no conditioned floor area" - and one further operative sentence that a roofer must plan around: "If the ice shield is not inspected, the contractor shall provide an affidavit that the ice shield materials were installed properly." That affidavit is the discharge route when the RCMC 15.04.280(A)(7) ice barrier inspection does not happen; see midroof_inspection_required. Section history: Ord. 6270, 2019; Ord. 6009, 2015; Ord. 5891, 2013; Ord. 5819, 2012. SCOPE LIMITS, stated because an earlier draft of this field overstated them: the Rapid City amendment contains NO 8-in-12 slope trigger, NO 36-inch measured-along-the-slope requirement, and NO enumerated list of covered roof coverings - the single dimensional requirement it imposes is the 24 inches inside the exterior wall line. Separately, RCMC 15.13.280 assumes ice barrier membrane may be present in existing assemblies, permitting an adhered existing ice barrier to remain in place and be covered with an additional layer of ice barrier membrane in accordance with Section R905.
City of Sioux Falls, South Dakota - Planning and Development Services, Building Services Division (City of Sioux Falls, South Dakota)
The City of Sioux Falls publishes its own "Asphalt Shingles Information Sheet" in its Homeowner's Construction Guides set, and that sheet carries the ice-barrier requirement for roofs in the city: an ice barrier of not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet used in place of normal underlayment, extending from the eave edge to a point not less than 24 inches inside the exterior wall line of the building. I opened both the homeowner-construction-guide copy of this sheet and the city's separately-linked "Asphalt Shingle Information Sheet" at https://www.siouxfalls.gov/files/assets/public/v/2/business-and-permits/ordinances/homeowner-construction/asphalt-shingle-information-sheet.pdf and confirmed both URLs currently serve the identical scanned document (byte-for-byte matching file); reading it in full (8 pages) found no printed date, so the two URLs are not two different editions. The document cites ASTM D7158/D3161 wind-classification and ASTM D1970 self-adhering-membrane standards and uses current IRC R905-series section language, consistent with the city's current 2021 IRC adoption rather than a stale pre-2021 edition. Note that under the 2021 IRC the ice barrier applies only where the jurisdiction has filled in Table R301.2(1) with "YES" for ice-barrier underlayment, which is a Sioux Falls-specific entry in the city's adopting ordinance rather than a South Dakota statewide determination - South Dakota sets no statewide ice-barrier rule.
City of Sturgis, South Dakota - Building Inspector's Office (City of Sturgis, Meade County, South Dakota)
Required, and it is one of only three local modifications Sturgis makes to the residential code. Section 2.02.01(1), inside the adoption itself, ends with the words "and figure 905.1.2 Ice and water barrier membrane required." The citation style is the City's own and is quoted as written: the provision it points at is Section R905.1.2 of the International Residential Code, Ice barrier, rather than a figure, and the same subsection uses "figure" the same loose way for its other two modifications. The requirement itself is unambiguous. Under the adopted 2021 code that means an ice barrier of at least two layers of underlayment cemented together, or a self-adhering polymer modified bitumen sheet, extending from the eave edge to a point at least 24 inches inside the exterior wall line of the building. Because Sturgis states the requirement in its own adopting ordinance rather than leaving it to the designation cell of Table R301.2, it does not depend on a climatic table the City has otherwise left largely blank.
City of Watertown, South Dakota - Building Inspection / Licenses & Permits (City of Watertown, South Dakota)
Table R301.2(1), as filled in by the city's amendment (Ord 18-27, Rev 12-28-18), states "Ice Shield Underlayment Required - Yes." The city separately amends IRC Sec. R905.1.2 (Ice Barrier), extending the required membrane from the base-code 24 inches to 36 inches inside the exterior wall line: "Section R905.1.2 Ice Barrier. Amend '24 inches (610 mm) inside the exterior wall line of the building' to '36 inches'."
City of Yankton, South Dakota - Community and Economic Development, Building Services & Permits (City of Yankton, South Dakota)
The city's Asphalt Shingle Roofing Guidelines handout states: "Ice and water shield installed minimum 24" inside exterior wall line. Underlayment installed per manufacturer's requirements based on slope and material type," and specifies a single layer of ice-dam protection membrane for roof slopes greater than 4:12 and a double layer for slopes between 2:12 and 4:12, illustrated with the city's own single-layer and double-layer underlayment diagrams.
Ice barrier required — Tennessee (1)
Ice barrier required — Wisconsin (3)
City of Green Bay, Wisconsin - Department of Community & Economic Development, Inspection Division (Building Permits & Inspections) (City of Green Bay, Wisconsin)
STATE-GOVERNED, NOT CITY-SET, but SCOPE-LIMITED BY ROOF SLOPE -- read the trigger before pricing the job. Wis. Admin. Code § SPS 321.28(4)(a) requires ice dam protection on shingled or shake roofs that extend over a heated area of the dwelling or an attached garage AND that have a slope of 4:12 or less; the protection must be sheet metal or a product labeled as meeting ASTM D1970. Wisconsin's UDC therefore does not impose the IRC's across-the-board cold-climate ice barrier on steeper roofs -- it is a Wisconsin-drafted rule, not an IRC clone. Extent, verbatim, SPS 321.28(4)(b): the ice dam protection "shall extend at least 30 inches up the roof slope from the roof edge and at least 12 inches up the roof slope beyond the inner face of the exterior wall." That is a different measurement convention from the IRC's "24 inches inside the exterior wall line" -- do not substitute IRC ice-barrier language on a Wisconsin job. Green Bay may not impose a different ice-barrier rule on a one- or two-family dwelling (Wis. Stat. § 101.65(1c)). The mandate genuinely exists in Wisconsin code, but it is the 4:12-or-less slope condition described here, not the bare yes-or-no answer, that governs a given roof. SCOPE -- the same Uniform Dwelling Code limits that govern the layer rule govern this one, because Wis. Admin. Code SPS 320.05 exempts work from the code as a whole rather than from any single section. SPS 320.05(1) excludes dwellings whose construction commenced before the code's effective date, and additions or alterations to such dwellings, unless the municipality has adopted chs. SPS 320 to 325 for that purpose -- whether Green Bay has done so is NOT established by this record. That date is June 1, 1980 for chs. SPS 320, 321, 323, 324 and 325 under SPS 320.03, while Wis. Stat. 101.615 states the cutoff as December 1, 1978; both are reported and neither is chosen. SPS 320.05(3) further excludes "repairs or maintenance to dwellings or dwelling units," and SPS 320.07(61) defines "repair" to include "the replacement of existing fixtures, systems or equipment with the equivalent" fixture, system or equipment. On a dwelling built before 1980, confirm with the City of Green Bay Inspection Division that the ice dam rule applies before pricing it in or out.
City of Madison, Wisconsin - Department of Planning, Community & Economic Development, Building Inspection Division (City of Madison, Wisconsin)
STATE-GOVERNED, NOT CITY-SET, AND SLOPE-CONDITIONED - read the scope carefully, it is narrower than the IRC/Minnesota rule. Wis. Admin. Code s. SPS 321.28(4)(a) requires that shingled or shake roofs that extend over a heated area of a dwelling or attached garage AND that have a slope of 4:12 or less be provided with ice dam protection, in the form of sheet metal or a product labeled as meeting the requirements of ASTM D1970. SPS 321.28(4)(b) sets the extent: the ice dam protection "shall extend at least 30 inches up the roof slope from the roof edge and at least 12 inches up the roof slope beyond the inner face of the exterior wall." Two cautions for Madison work: (1) on roof areas steeper than 4:12, the Uniform Dwelling Code does not itself impose an ice-barrier requirement, so a steep-slope reroof may be code-compliant without one (shingle manufacturers' own installation instructions may still require it, and SPS 321.28(3)(a) requires asphalt shingles to be installed per the manufacturer's instructions); (2) Wisconsin's "30 inches up the slope from the roof edge and 12 inches beyond the inner face of the exterior wall" is a different measurement convention from the IRC's "24 inches inside the exterior wall line" - do not substitute IRC ice-barrier language on a Wisconsin job. SCOPE -- the same Uniform Dwelling Code limits that govern the layer rule govern this one, because Wis. Admin. Code SPS 320.05 exempts work from the code as a whole rather than from any single section. SPS 320.05(1) excludes dwellings whose construction commenced before the code's effective date, and additions or alterations to such dwellings, unless the municipality has adopted chs. SPS 320 to 325 for that purpose -- whether Madison has done so is NOT established by this record. That date is June 1, 1980 for chs. SPS 320, 321, 323, 324 and 325 under SPS 320.03, while Wis. Stat. 101.615 states the cutoff as December 1, 1978; both are reported and neither is chosen. SPS 320.05(3) further excludes "repairs or maintenance to dwellings or dwelling units," and SPS 320.07(61) defines "repair" to include "the replacement of existing fixtures, systems or equipment with the equivalent" fixture, system or equipment. On a dwelling built before 1980, confirm with the City of Madison Building Inspection Division that the ice dam rule applies before pricing it in or out.
City of Milwaukee, Wisconsin - Department of Neighborhood Services (DNS) (City of Milwaukee, Wisconsin)
Governed statewide, not set by Milwaukee, and slope-conditioned. Wis. Admin. Code SPS 321.28(4)(a) requires ice dam protection on shingled or shake roofs that extend over a heated area of a dwelling or attached garage AND that have a slope of 4:12 or less; the protection must be sheet metal or a product labeled as meeting ASTM D1970. SPS 321.28(4)(b) sets the extent: the protection must extend at least 30 inches up the roof slope from the roof edge and at least 12 inches up the roof slope beyond the inner face of the exterior wall. On roofs steeper than 4:12 the Uniform Dwelling Code does not itself require an ice barrier. SCOPE -- the same Uniform Dwelling Code limits that govern the layer rule govern this one, because Wis. Admin. Code SPS 320.05 exempts work from the code as a whole rather than from any single section. SPS 320.05(1) excludes dwellings whose construction commenced before the code's effective date, and additions or alterations to such dwellings, unless the municipality has adopted chs. SPS 320 to 325 for that purpose -- whether Milwaukee has done so is NOT established by this record. That date is June 1, 1980 for chs. SPS 320, 321, 323, 324 and 325 under SPS 320.03, while Wis. Stat. 101.615 states the cutoff as December 1, 1978; both are reported and neither is chosen. SPS 320.05(3) further excludes "repairs or maintenance to dwellings or dwelling units," and SPS 320.07(61) defines "repair" to include "the replacement of existing fixtures, systems or equipment with the equivalent" fixture, system or equipment. On a dwelling built before 1980, confirm with the City of Milwaukee Development Center that the ice dam rule applies before pricing it in or out.
Ice barrier required — Wyoming (1)
Ice barrier not required (explicit) — Colorado (37)
Adams County - Building Safety Division (Adams County, Colorado (unincorporated))
"Installation of ice and water shield is not required in Adams County. If installed, it must meet the installation requirements set forth in the 2024 International Residential Code and the manufacturer's installation instructions."
Arapahoe County - Building Division (Arapahoe County, Colorado (unincorporated))
The county's own adopted climate-design-criteria table (Table R301.2(A), part of the 2021 IRC amendments in Resolution 21-394) lists "Ice Barrier Underlayment required: NO" for unincorporated Arapahoe County. Neither this table nor the county's 2024 Residential Re-roofing Guide amend or otherwise require an ice barrier.
Building Department - City of Florence (City of Florence, Colorado)
Florence Municipal Code Sec. 15.08.020, item S, amends Section R301.2 by the addition of its own design-criteria table; the printed cell reads "Ice Barrier Underlayment Required No."
City and County of Broomfield - Building Division (City and County of Broomfield, Colorado)
There has not been a substantial history of ice damming; therefore, no special treatment of eaves is required. Ice and water shields are not required by the code. Adequate ventilation and correct insulation can prevent ice damming from occurring.
City and County of Denver - Community Planning and Development (City and County of Denver, Colorado)
Table R301.2 Climatic and Geographic Design Criteria in Denver's Roofing Guide and Checklist lists "Ice Barrier Underlayment Required: No"; the guide states "Self-adhering bitumen installed at the eaves and rakes to two feet inside the exterior wall is NOT required."
City of Arvada - Building Division (City of Arvada, Colorado)
"While the City of Arvada does not require the additional underlayment requirements to protect against ice dams as a general rule, if the manufacturer requires additional measures then the City of Arvada will require it... the City of Arvada is not an area with a history of wide spread ice dams, therefore, we do not make it a requirement for all roof edges, however; we leave it up to the expert opinion of roofing contractors to determine if there has been a history of ice damming and then take the appropriate steps to protect affected areas when reroofing." (Re-Roofing Ice Dams Memo, Oct. 1, 2020, linked from the Re-Roofing page as "Ice Barrier (Ice and Water Shield) not required. See attached letter.")
City of Boulder - Building Permits & Inspections (City of Boulder, Colorado)
Table R301.2(1) climatic and geographic design criteria for the City of Boulder Residential Building Code states: "Ice barrier underlayment required = NO."
City of Brighton - Building Division (City of Brighton, Colorado)
Ice shield is not required (unless required by manufacturer).
City of Cañon City - Building Department (City of Cañon City, Colorado)
Cañon City Municipal Code Sec. 15.04.030 (Amendments), item I, amends Table R301.2(1) of the adopted IRC; the printed cell for "Ice Barrier Underlayment Required" reads "Not Required."
City of Castle Pines Building Department (City of Castle Pines, Colorado)
Ice Barrier is not required (item 6 of Residential Roofing Requirements).
City of Delta Building Department (City of Delta, Colorado)
An earned negative read from the instrument itself, not inferred from silence: the city's completed IRC Table R301.2(1) at Ch. 15.04.030(B) (Ord. 7, Sec. 1, 2021) states "Ice Barrier Underlayment Required: NO," and 2018 IRC R905.2.7.1 applies the ice-barrier requirement only where that table entry requires it. No other amendment in Ch. 15.04.030 touches R905.
City of Federal Heights Building Department (City of Federal Heights, Colorado)
Ice and water shield is not required unless specified per the manufacturer's installation instructions. This is the city's own adopted determination rather than an Adams County one: Ordinance No. 23-02, which adopts Federal Heights's technical codes, states that "Table R301.2 is repealed and reenacted to provide" a replacement table whose "Ice Shield Underlayment Requirement" reads "No" (alongside Ground Snow Load 40 lbs. per square foot, Seismic Design Category B, Weathering Severe, Frost Line Depth 36 Inches, Air Freezing Index 712, Mean Annual Temp 50.3F). Neighbouring Adams County jurisdictions reach the opposite conclusion, so this answer does not travel across the city boundary.
City of Fountain (permits via Pikes Peak Regional Building Department) (City of Fountain, Colorado)
The PPRBD regional code requires an ice barrier only for "properties that are above 7,000 ft. elevation"; Fountain sits at roughly 5,500 ft, below the trigger, so the requirement does not apply to properties in the city. (See 2023 PPRBC section RBC303.4.2 Table R301.2 footnote D and 2021 IRC section 905.1.2) Per PPRBD regional guidelines, which govern permits for Fountain. Fountain's own elevation (~5,538 ft) is well below the 7,000 ft trigger, so this rarely applies to Fountain addresses in practice.
City of Greeley - Building Inspection Division (City of Greeley, Colorado)
"Ice Barrier Underlayment Required: NO" (IRC Table R301.2(1) as added by § 22-87). Footnote (8) states the criterion: "In accordance with sections R905.1.2, R905.4.3.1, R905.5.3.1, R905.6.3.1, R905.7.3.1 and R905.8.3.1, where there has been a history of local damage from the effects of ice damming, the jurisdiction shall fill in this part of the table with 'yes.' Otherwise, the jurisdiction shall fill in this part of the table with 'no.'"
City of Lakewood - Building Division (City of Lakewood, Colorado)
An ice barrier underlayment is not required. This rests on Lakewood's own adopted table, not on a Jefferson County document: Lakewood Municipal Code 14.09.040 replaces Table R301.2 in its entirety, and the replacement table's "Ice Barrier required" column is filled in "NO" (alongside Ground Snow load 30 PSF, Seismic Design category B, Weathering Severe, Frost depth 36 inches, Air Freezing index 532, Mean Annual temp 51 F). No amendment to R905.1.2 appears anywhere in the city's Chapter 9 amendments, so nothing reinstates the requirement the table declines. Lakewood self-administers its own building permits, and neighbouring Jefferson County jurisdictions reach the opposite conclusion, so a roofer crossing a Lakewood boundary should not carry this answer with them. The city's residential roof/re-roof handout adds that Ice & Water Shield (or a similar self-adhering bitumen product) may be used in lieu of a double layer of felt underlayment for the entire roof when the slope is less than 4:12.
City of Lone Tree - Building Division (City of Lone Tree, Colorado)
Ice and water is not required (per General Requirements section).
City of Northglenn - Building Division (City of Northglenn, Colorado)
"Ice Barrier Underlayment Required: No" -- IRC Table R301.2(1) as filled in by Sec. 10-8-5(j) of the Northglenn Municipal Code (2021 IRC).
City of Thornton - Building Inspection Division (City of Thornton, Colorado)
Ice and water shield is not required unless specified in the shingle manufacturer's installation instructions.
City of Yuma - Building Inspection (City of Yuma, Colorado)
IRC Table R301.2(1) as amended by item (G) of Yuma Municipal Code § 15.10.030 lists "Ice Shield Underlayment Required No".
Delta County Planning and Community Development (Delta County, Colorado)
Outside the Highway 92 and Highway 50 Overlay Districts, Delta County has not adopted building codes for the unincorporated area, so the county imposes no ice-and-water-shield membrane requirement there. Within the two overlay districts, development is subject to the 2003 International Building Code (Resolution 2006-R-016 for Highway 92; Ordinance 2009-01 and Resolution 2009-R-055 for Highway 50); this record does not characterize the 2003 IBC's own ice-barrier provisions.
Mesa County Building Department (Mesa County, Colorado)
The Building Department's Reroof Policy (effective September 2025) states ice barrier membrane is not required along the eaves in areas of the county designated at a 30-psf ground snow load, which covers Grand Junction and the surrounding area, DeBeque, Little Park, the Glade Park Store area, and Gateway per the county's own snow and wind load table. The policy does not state a separate eave ice-barrier requirement for the county's higher-snow-load zones (40 to 100 psf, e.g. Mesa, Powderhorn, Collbran, the Vega Area, and Mesa Lakes); roofers working in those higher-elevation areas should confirm directly with the Building Department.
Saguache County Land Use Office (Saguache County, Colorado)
Saguache County has not adopted a building code. The county's Land Use FAQ states plainly that the county "does not have building codes," and the 2025 Land Development Code (effective November 18, 2025, read in full, all 271 pages) contains no IRC/IBC adoption and no provision requiring an ice-and-water-shield membrane anywhere in the document. No county-enforced ice barrier requirement applies.
Town of Akron - Building Department (Town of Akron, Colorado)
The Town of Akron's Building Department page states: "Ice and water guard: NOT required by the Town of Akron; please check with your insurance company, as this may be a requirement."
Town of Elizabeth Building Department (Town of Elizabeth, Colorado)
Table R301.2(1) as completed by § 18-2-40(j) prints "Ice barrier Underlayment Required" as "NO".
Town of Erie - Building Division (Town of Erie, Colorado)
Ice shield is not required (unless required by manufacturer).
Town of Foxfield Building Permits (SAFEbuilt Inc.) (Town of Foxfield, Colorado)
Table R301.2(1) as filled in by § 18-2-30, item (10), prints "Ice Shield Underlayment Required" as "NO." This corroborates the Town's separately cited SAFEbuilt Residential Reroofing Requirements handout, which independently states "ice-and-water shield is not required."
Town of Kersey Building Inspection Department (Town of Kersey, Colorado)
Kersey Municipal Code § 18-45(13) fills in IRC Table R301.2(1) and prints, in its single data row, "Ice Barrier Underlayment Required: No" (the full row reads "30psf 115 No B Severe 30 in. Slight to Moderate 1 No * 1000 45°F"). That is the Town's own adopted, codified instrument and it governs. A "2024 IRC Residential Re-roofing" guide linked from the Town's Building Permit page states the opposite - "ICE AND WATER SHIELD IS REQUIRED ON ALL ROOFS" - but that document is not a Kersey instrument: it is a SAFEbuilt handout distributed unchanged to multiple client towns (the file Kersey links is byte-for-byte identical to the copies published by Dacono and Windsor, and its own text carves out "THE TOWN OF TIMNATH" by name). A shared handout cannot establish a Kersey-specific climatic value, so the codified table's "No" is what this record reports.
Town of Kiowa - Building Department (Town of Kiowa, Colorado)
The Town's Building Department page states, under Section 18-2-40, IRC Table R301.2 requirements: "ice barrier underlayment is not required."
Town of Larkspur - Building Department (Town of Larkspur, Colorado)
Larkspur Municipal Code § 18-6-40(13)'s Table R301.2(1) amendment prints "No" in the "Ice Barrier Underlayment Required" column.
Town of Log Lane Village Building Inspector (Town of Log Lane Village, Colorado)
The Town's own Table R301.2(1), Climatic and Geographic Design Criteria, as completed by Sec. 6-29(4)(c) (Ord. No. 04-11, 6-8-2011), answers the table's Ice Barrier Underlayment Required column "No" for Log Lane Village.
Town of Lyons - Building Department (Town of Lyons, Colorado)
Table R301.2(1) as completed by § 18-3-40 prints "Ice Barrier Underlayment Required" as "NO".
Town of Paonia - Building Department (Town of Paonia, Colorado)
Paonia Municipal Code § 18-2-30(k)'s Table R301.2(1) amendment prints "Ice Barrier Underlayment: No" as one of the added climatic design values.
Town of Parker - Building Division (Town of Parker, Colorado)
Town of Parker Building Division Re-Roofing Requirements handout states "Ice and Water Required- No, not applicable." for asphalt shingle re-roofs (all other roof materials must meet code or manufacturer specs).
Town of Saguache Building Site Permits (Town of Saguache, Colorado)
The Town of Saguache's codified Municipal Code — all twelve substantive chapters, read in full, current through Ordinance No. 2023-2 — contains no adopted IBC/IRC edition and no chapter addresses an ice-and-water-shield membrane requirement, so none is enforced by the Town.
Town of Stratton - Building Permits (Town of Stratton, Colorado)
The Town's only adopted construction code is the 2025 Colorado Wildfire Resiliency Code, adopted by reference via Ordinance No. 94B (no IRC/IBC has been adopted). The CWRC, read in full, contains no ice-barrier or ice-and-water-shield provision anywhere in its text.
Town of Westcliffe - Building Department (Town of Westcliffe, Colorado)
Westcliffe Municipal Code § 3-2-2(B)(3)'s Table R301.2(1) insert prints "Ice Barrier Underlayment NO" as the town's filled-in value for this row.
Weld County - Building Inspection Division (Weld County, Colorado (unincorporated))
Weld County's amended IRC Table R301.2(1) (Climatic and Geographic Design Criteria, Sec. 29-2-30.B, amending Table 301.2) lists "ICE SHIELD UNDER-LAYMENT = NO" as the countywide determination.
Ice barrier not required (explicit) — Arkansas (1)
Ice barrier not required (explicit) — Indiana (2)
City of Carmel, Indiana - Department of Community Services, Building and Code Services (Building Safety Office) (City of Carmel, Indiana)
STATE-GOVERNED, NOT CITY-SET, and county-conditional -- Carmel is in Hamilton County, which the Indiana-amended IRC Table R301.2(1) at 675 IAC 14-4.4-5 marks "Ice Shield Underlayment Required: No." An ice barrier is therefore NOT categorically mandated by the table in Carmel, unlike the northern lake-effect counties (for example Allen County / Fort Wayne, marked Yes). It can still be required in Carmel by a second, independent route: the Indiana State Building Commissioner's guidance memo "Ice/Water Shield & Metal Drip Edge in Class 2 Construction with Asphalt Shingles" (Craig E. Burgess, AIA NCARB CPE CBI LEED AP, 2020-02-25) explains that two layers of rule combine -- "there are specific counties in which it is always required (per Table R301.2(1)), and specific counties in which it is required only when the roofing manufacturer's written installation instructions require it (per Sections R903.1, R904.1 and R905.1)." Hamilton County falls in the second group, and most major shingle manufacturers' written instructions do call for an ice barrier in central Indiana. Where it is required, 2018 IRC Section R905.1.2 governs its extent: the barrier "shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet ... and extend from the lowest edges of all roof surfaces to a point not less than 24 inches inside the exterior wall line of the building," with an exception for "detached accessory structures not containing conditioned floor area."
City of Indianapolis / Marion County, Indiana - Department of Business and Neighborhood Services (BNS), Construction Services (City of Indianapolis / Marion County, Indiana)
Not categorically required in Marion County by the climatic table, but commonly required in practice by the manufacturer-instructions rule -- read both halves. STATE-GOVERNED, NOT CITY-SET. Indiana's replacement Table R301.2(1) at 675 IAC 14-4.4-5 sets "Ice Shield Underlayment Required" to "No" for Marion County (unlike, for example, Allen County / Fort Wayne, where the same table says Yes), and Indianapolis's own Homeowner's Building Permit Guide reprints that "No" in its Marion County table row. The Indiana State Building Commissioner's guidance memo "Ice/Water Shield & Metal Drip Edge in Class 2 Construction with Asphalt Shingles" (2020-02-25) is explicit that two layers of rule combine: "there are specific counties in which it is always required (per Table R301.2(1)), and specific counties in which it is required only when the roofing manufacturer's written installation instructions require it (per Sections R903.1, R904.1 and R905.1)." Marion County is in the second group: the table does not mandate an ice barrier, but IRC R903.1/R904.1/R905.1 independently require roof coverings to be installed per the manufacturer's written installation instructions, and where those instructions call for an ice barrier in a central-Indiana climate it becomes mandatory on that job. Where an ice barrier is triggered, the unamended 2018 IRC R905.1.2 extent applies: "The ice barrier shall consist of not fewer than two layers of underlayment cemented together, or a self-adhering polymer-modified bitumen sheet ... and extend from the lowest edges of all roof surfaces to a point not less than 24 inches inside the exterior wall line of the building. ... Exception: Detached accessory structures not containing conditioned floor area."
Ice barrier not required (explicit) — Kansas (8)
Butler County Community Development Department (Butler County, Kansas)
"Ice Barrier Underlayment Required: No" (Table R301.2(1), Climatic and Geographic Design Criteria, as amended by the Butler County Building Code, Article 6, Sec. 603(i), adopted by the Board of County Commissioners via Resolution 16-06, February 23, 2016).
City of Andover Building & Inspections Department (City of Andover, Kansas)
"Ice Barrier - None Required" (Table R301.2(1), Climatic and Geographic Design Criteria, Wichita-Sedgwick County Unified Building and Trade Code, "Wichita Jurisdiction" terms, which the City of Andover elected to opt into in full via Ordinance No. 1957, Sec. 4-301, adopted May 13, 2025).
City of Derby - Building Trades & Inspections (City of Derby, Kansas)
Table R301.2(1) Climatic and Geographic Design Criteria, as amended by Ordinance No. 2623 (Section N, amending 2024 IRC Section R301.1), lists "Ice Barrier None Required." The ordinance's table footnote directs: "For footnotes, refer to Table R301.2(1) of the 2024 International Residential Code," i.e. Derby did not write a custom ice-damming footnote and instead adopts the base IRC's own "history of local damage" trigger language, filled in as not required for this table.
City of Haysville - Public Works Department (City of Haysville, Kansas)
"Ice Barrier - None Required" (Table R301.2(1), Climatic and Geographic Design Criteria, as amended within Section 4-301 of the Code of the City of Haysville, Kansas, adopting the International Residential Code, 2018 Edition).
City of Topeka - Development Services Division (City of Topeka, Kansas)
IRC Table R301.2(1) as substituted by the City of Topeka lists "NO" in the "Ice Barrier Underlayment Required" column. Footnote h to the table states: "In accordance with Sections R905.2.7.1, R905.4.3.1, R905.5.3.1, R905.6.3.1, R905.7.3.1 and R905.8.3.1, where there has been a history of local damage from the effects of ice damming, the jurisdiction shall fill in this part of the table with 'YES.' Otherwise, the jurisdiction shall fill in this part of the table with 'NO.'" (Topeka Municipal Code 14.55.230, IRC Table R301.2(1), enacted by Ord. 20467 § 9, 12-5-23.)
City of Wichita - Metropolitan Area Building & Construction Department (MABCD) (City of Wichita, Kansas)
Table R301.2(1) Climatic and Geographic Design Criteria, as amended by Sec. 2.4.115 of the Wichita/Sedgwick County Unified Building & Trade Code (UBTC), Article 2, Section 4, lists "Ice Barrier - None Required." Footnote h to the amended table states the jurisdiction fills this cell in with "YES" only "where there has been a history of local damage from the effects of ice damming," and "Otherwise, the jurisdiction shall fill in this part of the table with 'NO.'"
Sedgwick County - Metropolitan Area Building & Construction Department (MABCD) (Sedgwick County, Kansas (unincorporated))
Table R301.2(1) Climatic and Geographic Design Criteria, as amended by Sec. 2.4.115 of the Wichita/Sedgwick County Unified Building & Trade Code (UBTC), Article 2, Section 4, lists "Ice Barrier - None Required." Footnote h to the amended table states the jurisdiction fills this cell in with "YES" only "where there has been a history of local damage from the effects of ice damming," and "Otherwise, the jurisdiction shall fill in this part of the table with 'NO.'"
Shawnee County - Land Use & Development Department (Shawnee County, Kansas (unincorporated))
Shawnee County's own building-code page (https://www.snco.gov/ludev/building_code.php) states: "Shawnee County adopts by reference Title 14, Building and Construction of the City of Topeka Code as the Shawnee County Building Code. As currently in effect, this includes" Chapter 14.55 (International Residential Code) among the incorporated chapters; Chapter 14.55 is not among the seven chapters the county's resolution excludes. Under that incorporation, IRC Table R301.2(1) as substituted by the City of Topeka (TMC 14.55.230, Ord. 20467 § 9, 12-5-23) lists "NO" in the "Ice Barrier Underlayment Required" column, per footnote h ("where there has been a history of local damage from the effects of ice damming, the jurisdiction shall fill in this part of the table with 'YES.' Otherwise ... 'NO.'").
Ice barrier not required (explicit) — Missouri (7)
City of O'Fallon, Missouri - Building Division (City of O'Fallon, Missouri)
Table R301.2(1) Climatic and Geographic Design Criteria, as currently codified (Article X, 2021 IRC as amended by Ord. No. 7133, 9-12-2024): row "ICE BARRIER UNDERLAYMENT REQUIRED" = "No." This directly corroborates the city's separate 2017 re-roofing guide, which states: "Ice and Water Shield: Ice and water shield (R905.2.7) is not required per Table R301.2(1) as completed and adopted by the City." Confirmed from the current (2021 IRC) table itself, not just the older guide.
City of St. Louis, Missouri - Building Division (City of St. Louis, Missouri)
St. Louis's own amendment to Table R301.2(1) (Climatic and Geographic Design Criteria), codified in Chapter 25.11, Sec. 25.11.020 (Chapter 3 amendments), lists: "ICE SHIELD UNDERLAYMENT REQUIRED (j): Not Required" (alongside Ground Snow Load 20 psf, Winter Design Temp 5F, Air Freezing Index 963 F-days). This is an explicit, amended local table entry -- not silence or omission -- stating the ice-barrier underlayment provision of IRC R905.1.2 does not apply in the City of St. Louis. This is notably different from nearby Kansas City and Independence, MO, both of which amend the same table to REQUIRE ice barrier underlayment.
City of St. Peters, Missouri - Building Department (City of St. Peters, Missouri)
"For asphalt shingle roofs, the ice barrier mentioned in IRC Section R905.2.7 Ice Barrier, is not required by IRC Table R301.2 as amended and adopted by the City of St. Peters." (City of St. Peters "Residential Re-Roofing Requirements," Building Department, "Revised 3/27/2024.") Directly corroborated by the currently codified Section 504.040(A)(25), which amends Table R301.2 and lists: "Ice barrier underlayment on the roof = none."
City of Wentzville, Missouri - Building Division (City of Wentzville, Missouri)
Sec. 500.080(9), amending Table R301.2(1) Climatic and Geographic Design Criteria (currently codified, 2021 IRC as amended, most recently amended 1-24-2024): row "Ice Barrier Underlayment Required" = "NO." Sourced directly from the city's own currently codified table, not from a separate guidance document.
St. Charles County, Missouri - Division of Building and Code Enforcement (St. Charles County, Missouri)
Table R301.2 (Climatic and Geographic Design Criteria) as filled in by the county's residential code amendment lists "Ice Barrier Underlayment Required" as "NO" for St. Charles County.
St. Louis County - Department of Transportation and Public Works (Building Division) (St. Louis County, Missouri)
St. Louis County's own amended climatic design table states the requirement is NOT triggered. The county's Chapter 1115 amendment to IRC Table R301.2(1) "Climatic and Geographic Design Criteria" lists, under the "ICE BARRIER UNDERLAYMENT REQUIRED" column, the value "NO" for St. Louis County (footnote h cross-references Sections R905.1.2, R905.4.3.1, R905.5.3.1, R905.6.3.1, R905.7.3.1 and R905.8.3.1, and states the jurisdiction fills this cell in as YES/NO "where there has been a history of local damage from the effects of ice damming"). This is corroborated word-for-word by three separate county publications: the Single-Family Dwelling Design Checklist ("Ice Barrier underlayment is not required (R905.1.2; SLCO Revised Ordinance Table R301.2(1))"), the Residential Room Additions guide ("Ice Barriers are not required by St. Louis County (R905.1.2; SLCO Revised Ordinance Table R301.2(1))"), and the amended-code ordinance document itself (the Table R301.2(1) entry). The county states this affirmatively; it is not simply an unanswered question.
St. Louis County, Missouri Department of Transportation and Public Works - Building Permit Section (permitting authority for the City of Chesterfield, Missouri, by contract) (City of Chesterfield, Missouri)
Chesterfield's own Municipal Code, Chapter 500, Table R301.2(1) Climatic and Geographic Design Criteria (as filled in/amended by the city's own ordinance, Attachment B "1116.103 - Amendments to the International Residential Code... Chapter 3 Building Planning"), lists "Ice Barrier Underlayment Required" as "NO" for Chesterfield. Independently corroborated by St. Louis County's own Re-Roofing Checklist for contracting municipalities: "Ice Barrier underlayment is not required (R905.1.2; SLCO Revised Ordinance Table R301.2(1))." Two independent official sources agree Chesterfield does NOT require ice barrier/ice-and-water-shield underlayment as a blanket rule (footnote h ties this to local history of ice-damming damage, which Chesterfield and St. Louis County have both filled in as "NO").
Ice barrier not required (explicit) — New Mexico (2)
City of Albuquerque, New Mexico - Building Safety Division (Planning Department) (City of Albuquerque, New Mexico)
Earned from Albuquerque's own printed design table, not inferred from climate or region. The state rule hands this row to the AHJ - 14.7.3.11(A)(1) NMAC amends footnote f of IRC Table R301.2 to read "The authority having jurisdiction shall fill in this part of the table with the seismic design category determined from Section R301.2.2.1 or information from the U.S.G.S. software Design Values for Buildings found online." Albuquerque filled it in. The Uniform Administrative Code of the City of Albuquerque (2024 Edition), Chapter 3 addition to R301.2, prints "Table R301.2 Climatic and Geographic Design Criteria" with a column headed "Ice Shield Under-Layment Required" and enters "N/A" in it. No ice-barrier underlayment is designated as required for Albuquerque by the City's own table, and neither the Uniform Administrative Code nor 14.7.3 NMAC imposes one elsewhere. The 2024 Uniform Administrative Code was read in full and contains no ice-barrier or ice-shield provision beyond that table cell.
City of Las Cruces, New Mexico - Community Development Department (Building Section) (City of Las Cruces, New Mexico)
Earned from the City's own enacted design table. The state rule hands this row to the AHJ - 14.7.3.11(A)(1) NMAC amends footnote f of IRC Table R301.2 so that "The authority having jurisdiction shall fill in this part of the table" - and Las Cruces filled it in by ordinance: the Table R301.2(1) printed at Section 30-722(B)(10) of the Las Cruces Municipal Code enters "No" in the "Ice Barrier Underlayment" column. That is an explicit negative in the City's own completed table, not an inference from climate. Neither Chapter 30's building-standards division (Sections 30-721 and 30-722, the City's complete code-adoption and amendment instrument) nor 14.7.3 NMAC imposes an ice-barrier requirement elsewhere.
Ice barrier not required (explicit) — Tennessee (9)
City of Clarksville Building & Codes Department (City of Clarksville, Tennessee)
Table R301.2(1), Climatic and Geographic Design Criteria, as replaced by the City of Clarksville's residential-code amendments (Code of Ordinances Sec. 4-801, current through Ord. No. 40-2020-21), lists "Ice Barrier Underlayment Required" as "No" for the city. No separate ice-barrier provision appears elsewhere in the city's local amendments.
City of Johnson City Building Division (City of Johnson City, Tennessee)
The City of Johnson City's own published Design Criteria sheet, distributed by the Building Division through its Contractor Requirements and Information document center for designers, lists "Ice Barrier Underlayment Required = No" alongside the city's other Table-R301.2(1)-type design values (ground snow load, seismic design category, wind speed, frost line depth, weathering, termite risk). No other provision in the city's adopted 2018 IRC amendments (Code of Ordinances section 12-301(2), read in full) addresses ice barrier underlayment.
City of Knoxville Plans Review and Inspections (City of Knoxville, Tennessee)
Table R301.2(1) of the City of Knoxville's Residential Building Code amendments (Code of Ordinances Sec. 6-42, current through Ordinance No. O-125-2024, the same ordinance that adopted the 2024 IRC) lists "Ice Barrier Underlayment Required" as "No" for the city. No separate ice-barrier provision appears elsewhere in the city's local amendments.
City of Murfreesboro Building and Codes Department (City of Murfreesboro, Tennessee)
Ordinance 18-O-71, Section 4(N), amends Table R301.2(1), Climatic and Geographic Design Criteria, by inserting the city's specific values into the table, including the row "Ice Barrier Underlayment Required" set to "No." No separate ice-barrier provision appears elsewhere among the ordinance's local amendments.
Knox County, Tennessee - Codes Administration (Knox County, Tennessee)
The county's own 2018 IRC amendments document, read in full, amends Table R301.2(1) (Climatic and Geographic Design Criteria) with the instruction "Insert 'No' in the table for Ice Barrier Underlayment Required." No other provision in either amendment document adds an ice-barrier or ice-and-water-shield requirement.
Memphis and Shelby County Office of Construction Code Enforcement (Division of Planning and Development) (City of Memphis, Shelby County, Tennessee)
The office's Policy for Roof Installations answers in Q&A form: "Does Shelby County require an ice and water shield (barrier)? No, per our local amendment." Confirmed again: "there are no amendments to chapter 9 of this code other than we do not require an ice barrier per section 905.1.2." This is a LOCAL AMENDMENT removing the 2021 IRC's default ice-barrier requirement -- consistent with Memphis's climate (ice-dam formation is not a design concern there).
Metropolitan Government of Nashville & Davidson County, Tennessee - Department of Codes and Building Safety (Codes Administration) (Metropolitan Government of Nashville and Davidson County, Tennessee)
Table R301.2 of Metro Ordinance BL2025-898 (Metropolitan Code of Laws Title 16, ch. 16.08, Sec. 16.08.014, item F, Amendments to the 2024 International Residential Code) lists "Ice Barrier Underlayment Required" as "No" for Nashville and Davidson County. No separate ice barrier provision appears elsewhere in Metro's local IRC amendments (Sec. 16.08.014, items A through P, read in full).
Shelby County, Tennessee - Division of Planning and Development, Construction Code Enforcement (Shelby County, Tennessee)
Shelby County's own "Policy for Roof Installations" FAQ states: "Does Shelby County require an ice and water shield (barrier)? No, per our local amendment," citing IRC Section 905.1.2. The same document states this is the only provision of IRC Chapter 9 the county has amended. The county's own Table R301.2 (Climatic and Geographic Design Criteria), as amended by Joint Ordinance No. 569, lists "Ice Barrier Underlayment Required" as "No."
Town of Smyrna, Tennessee - Building Safety Department (Town of Smyrna, Rutherford County, Tennessee)
Not required. The Town of Smyrna's Climatic and Geographic Design Criteria sheet lists "Ice Barrier No", and the same entry appears in its line-by-line modifications as part of the amendment to Table R301.2. That entry is the operative act rather than a description of the weather: the adopted residential code conditions its ice barrier requirements on a history of local damage from ice damming as designated in Table R301.2, and Smyrna has made the designation in the negative. A roofer is free to install an ice and water barrier as good practice or because a shingle manufacturer's warranty calls for it, but the Town does not require one.
Ice barrier not required (explicit) — Texas (11)
City of Arlington - Planning & Development Services Department (City of Arlington, Texas)
Ice barrier underlayment is not required in Arlington: the city's own amendments to the 2021 IRC do not require it, and the city cites the region's lack of a history of ice damming. Residential roof decking, drip edge, and ventilation requirements are enforced per the 2021 IRC. (City of Arlington Re-Roof Permits & Inspections technical bulletin.)
City of Carrollton - Building Inspection (City of Carrollton, Texas)
Table R301.2(1), Climatic and Geographic Design Criteria, as amended by the city's 2024 I-Codes amendments (Ordinances 4265, adopted 7-8-2025, and 4290, adopted 12-2-2025, codified at ecode360 Ch. 150 Sec. 150.016), lists "ICE BARRIER UNDERLAYMENT: No" for Carrollton (Ground Snow Load 8 lb/ft2, Winter Design Temp 22F, Air Freezing Index 150). Architect-verified directly from the codified amendment attachment, 2026-07-18.
City of Fort Worth - Development Services Department (City of Fort Worth, Texas)
Table R301.2(1), Climatic and Geographic Design Criteria, as amended by the City's adopted IRC amendments, lists "Ice Barrier Underlayment Required" as "No" for Fort Worth (2021 IRC amendments, Ord. No. 25383-03-2022, Sec. 7-62, passed 3-8-2022, eff. 4-1-2022).
City of Grapevine - Building Inspection Department (City of Grapevine, Texas)
Table R301.2 (Climatic and Geographic Design Criteria) as adopted in the city's Residential Code amendments lists "ICE BARRIER: No" for Grapevine (City of Grapevine, Chapter 7 Buildings and Construction, Article V Residential Code, Sec. 7-140/7-142).
City of Lewisville - Building Services Division (City of Lewisville, Texas)
City of Lewisville's amendments to the 2021 International Residential Code (Code of Ordinances Sec. 4-32) fill in Table R301.2(1), Climatic and Geographic Design Criteria, for the city: the "ICE BARRIER UNDERLAYMENT REQUIRED" column is set to "No" (row also reads ground snow load 5 lb/ft, wind speed 115 mph 3-sec gust / 76 mph fastest mile, seismic design category A, winter design temp 22 deg F, flood hazards "Local Code", air freezing index 150, mean annual temp 64.9 deg F).
City of North Richland Hills - Building Inspection Department (City of North Richland Hills, Texas)
Table R301.2(1), Climatic and Geographic Design Criteria, as amended by the City's adopted IRC amendments, lists "Ice Barrier Underlayment Required" as "No" for North Richland Hills (2024 IRC amendments, Ordinance No. 3947, Sec. 98-142, adopted 2/9/2026).
City of Rowlett - Building Safety Department (City of Rowlett, Texas)
Table R301.2(1) "Climatic and Geographic Design Criteria," as amended by Exhibit A (International Residential Code Amendments, 2021 Ed.) to the City of Rowlett's adopted-code ordinance, lists "No" in the Ice Barrier Under-Layment column (alongside Winter Design Temp 22°F, Air Freezing Index 150, Ground Snow Load 5 lb/ft).
City of San Antonio Development Services Department (DSD) (City of San Antonio, Texas)
San Antonio's own Table R301.2 (as amended by Sec. 10-37 of City Code Chapter 10, 2024 IRC local amendments, Ordinance No. 2025-01-30-0075) lists "ICE BARRIER UNDERLAYMENT REQUIRED" as "NO" for the city (same table row also shows Winter Design Temp 30 degrees F, Air Freezing Index 16, Mean Annual Temp 68.7 degrees F -- consistent with a no-ice-barrier climate).
Denton County - Development Services (Denton County, Texas)
Denton County has adopted no building code that reaches reroofing an existing single-family home. Its Fire Code, the 2021 International Fire and Building Code, carves those homes out of its own scope at Section 101.2, Exception 1, which provides that one- and two-family dwellings and townhomes of not more than two attached units "shall comply with Local Government Code 233 Subchapter F 'Residential Building Code'" instead. Subchapter F in turn reaches only new residential construction, which Texas Local Government Code Section 233.151 defines as a single-family house or duplex built on a vacant lot, or an addition increasing an existing home's square footage or value by more than 50 percent. Ordinary roof repair and replacement is neither. The county imposes no ice barrier or ice-and-water-shield requirement on that work. Note that under Texas Local Government Code Section 233.153(c) a municipality's own building code controls inside that municipality's extraterritorial jurisdiction, so a home in an ETJ may be governed by a city's code rather than by the county.
Town of Flower Mound - Building Inspections Department (Town of Flower Mound, Texas)
Table R301.2(1) "Climatic and Geographic Design Criteria," as amended by Exhibit F (Local Amendments to the 2024 International Residential Code) to the Town of Flower Mound's adopted-code ordinance, lists "No" in the Ice Barrier Under-Layment column (alongside Winter Design Temp 22°F, Air Freezing Index 150, Ground Snow Load 9 lb/ft).
Travis County Development Services (Transportation and Natural Resources) (Travis County, Texas)
Travis County has adopted no building code that reaches reroofing an existing single-family home. Travis County Code Chapter 480, Residential Construction Standards, applies by its Section 480.003 only to "new residential construction," which Section 480.002 defines as "Residential construction of a single-family house or duplex on a vacant lot" or "Construction of an addition to an existing single-family house or duplex, if the addition will increase the square footage or value of the existing residential building by more than 50 percent." Ordinary roof repair and replacement is neither. The county's Fire Code, Chapter 201, is capped by the same statutory scope and does not reach these dwellings either. The county imposes no ice barrier or ice-and- water-shield requirement on that work. Note that under Texas Local Government Code Section 233.153(c) a municipality's own building code controls inside that municipality's extraterritorial jurisdiction, so a home in an ETJ may be governed by a city's code rather than by the county.
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