Bonneville County, Idaho - Planning, Zoning, and Building Department

Bonneville County, Idaho

county

605 N Capital Ave, Idaho Falls, ID 83402

Required

Required

Bonneville County's Planning, Zoning, and Building Department runs applications through a Cityworks Online portal. The County's own department page states that "Starting January 20, 2026, Bonneville County will be processing Electrical and Plumbing Permits and performing the inspections related to those permits. The State of Idaho will no longer provide these services" -- a change to who administers electrical and plumbing work, not building or roofing, which the County has always handled itself. TWO THINGS THIS RECORD CANNOT ANSWER FOR YOU, AND BOTH ARE WORTH ASKING WHEN YOU APPLY: the County has not published a fee schedule, an exempt-work list, or an inspection-stage schedule for roofing on its own website (its online building-permit, inspection and fee pages are dynamic widgets that returned no content to this research), so the exact permit fee, whether a mid-roof inspection stop applies, and any repair threshold below which a permit is not required should all be confirmed directly with the Department; and the County has not published its own local design-criteria table (ground snow load, wind speed and the rest), so ask before specifying a roof to those figures. CONTACT: 357 Constitution Way, Idaho Falls, ID 83402 (mailing address 605 N Capital Ave); phone 208-524-7920; fax 208-529-1330; email [email protected]; office hours weekdays 8am-5pm excluding holidays.

LOCALLY ENACTED, ON A STATE-MANDATED EDITION, WITH NO COUNTY AMENDMENTS OF ITS OWN. The operative instrument is Bonneville County Code 150.01, Codes Adopted (Ord. 239-21, passed 6-23-2021; amended by Ord. 278-26 and Ord. 279-26, both passed 1-8-2026), which reads in relevant part: "The approved editions of the following nationally recognized codes, as adopted by the state or the State Building Code Board, are adopted as the Official Building Codes of the county," naming the 2018 Edition International Building Code and the 2018 Edition International Residential Code, Parts I through VI and IX, among the ten codes listed. The section closes: "All amendments made by the state or the State Building Code Board and the State Fire Marshal's office are included" -- so the County's own amendment list is empty, and the chapter as a whole confirms it: Chapter 150, Building Regulations, runs to exactly three sections (150.01 Codes Adopted, 150.02 Safety Assessments of Buildings and Structures, 150.99 Penalty), all read in full, with no technical amendment section at all. Section 150.01(C) also exempts agricultural buildings from the adopted codes, subject to the County Assessor's determination that the property is land actively devoted to agriculture under Idaho Code 63-604, tracking the state exemption at Idaho Code 39-4116(5). THE STATE FRAMEWORK: Idaho's residential code is set by the Idaho Building Code Board, not by the county. IDAPA 24.39.30.600.03 adopts the "International Residential Code, 2018 Edition ... Parts I, II, III, and IX of the 2018 Edition for one (1)- and two (2)-family dwellings," effective July 1, 2024, together with a list of state amendments; Idaho Code 39-4116(2) requires a local government that issues building permits and performs code enforcement to adopt the Idaho residential code parts I-III and IX by ordinance, and bars it from adopting provisions of a later IRC edition the Board has not adopted. Roofing sits in Part III and is included. Idaho Code 39-4116(6): "Permits shall be governed by the laws in effect at the time the permit application is received."

Required — Neither the State of Idaho nor Bonneville County modifies the model rule. IDAPA 24.39.30.600.03 -- the Idaho Building Code Board's complete list of state amendments to the 2018 International Residential Code, seventeen items, read in full -- contains no amendment to Chapter 9, Roof Assemblies. Bonneville County Code 150.01, Codes Adopted, adopts the 2018 IRC and states in terms that the only amendments to it are the state's; the whole of Chapter 150, Building Regulations -- three sections in total -- was read and adds nothing of its own. The base 2018 IRC drip-edge requirement for asphalt shingle roofs (Section R905.2.8.5) therefore applies unmodified in unincorporated Bonneville County. Confirm the flashing detail and the fastener spacing against the shingle manufacturer's printed instructions as well, which the code makes binding. About drip edge

Not required — No impact-resistance mandate applies in unincorporated Bonneville County. IDAPA 24.39.30.600.03 -- the State of Idaho's complete list of amendments to the 2018 International Residential Code, read in full -- contains no amendment to Chapter 9, Roof Assemblies, and no UL 2218, Class 4 or FM 4473 impact-rating reference anywhere in the rule. Bonneville County Code Chapter 150, Building Regulations, was read in full -- all three of its sections -- and states that it adds no amendments of its own beyond adopting the state's; it contains no UL 2218, Class 4, Class IV or FM 4473 reference either, and no hail provision. Neither the state's nor the County's adopted code imposes an impact-resistant roof covering requirement. An insurance discount for impact-rated shingles, where a carrier offers one, is a matter between the homeowner and the insurer and is not a code requirement.

No dollar figure and no size threshold is published by the County for a residential re-roof. Bonneville County Code 150.01, Codes Adopted, read in full alongside the whole of Chapter 150 -- Building Regulations, which is only three sections long (150.01 Codes Adopted, 150.02 Safety Assessments of Buildings and Structures, 150.99 Penalty) -- adopts the 2018 International Residential Code and states that "all amendments made by the state or the State Building Code Board and the State Fire Marshal's office are included," adding none of its own. Neither that chapter nor the State of Idaho's own amendment list to the 2018 IRC (IDAPA 24.39.30.600.03, seventeen items, read in full) adds a roofing exemption to the permit-exempt-work list: the two amendments the state makes there change a dimension in one existing exempt item and add flag poles as a new one, and neither reaches roofing. ONE STATE FIGURE LOOKS LIKE A THRESHOLD AND IS NOT. IDAPA 24.39.30.002.02 defines "Minor Alteration" to include "roof repairs involving installation of less than one hundred (100) square feet of new roof covering," but the rule states in the same breath that the definition "is used for the purpose of administering annual permits," and Section 500.01 explains what that means: an annual permit is a standing permit the Division may issue "to any state agency or state governmental organization regularly employing one (1) or more qualified trade persons," in place of a separate permit for each minor alteration those in-house crews make. It is an institutional bookkeeping mechanism for state agencies, not a threshold a homeowner or a roofing contractor can rely on to skip a permit on a Bonneville County house. The County publishes no fee schedule or exempt-work list of its own online to check that figure against, so confirm the threshold, if any, with the Planning, Zoning, and Building Department directly before assuming a small repair needs no permit.

BONNEVILLE COUNTY PUBLISHES NO LOCAL DESIGN-CRITERIA TABLE OF ITS OWN, UNLIKE SEVERAL OF ITS NEIGHBORS. Table R301.2(1) of the International Residential Code -- the climatic and geographic design criteria table that sets ground snow load, wind speed, seismic design category, frost depth and the rest -- is a blank table the model code leaves for each adopting jurisdiction to fill in. The State of Idaho's own amendment list to the 2018 IRC, IDAPA 24.39.30.600.03, seventeen items, read in full, does not amend or otherwise populate that table for any jurisdiction; Idaho leaves it to the local adopting authority. Bonneville County Code Chapter 150, Building Regulations, was read in full -- all three of its sections, 150.01 Codes Adopted, 150.02 Safety Assessments of Buildings and Structures, and 150.99 Penalty -- and none of them states a ground snow load, wind speed, seismic category, frost depth or any other Table R301.2(1) figure for the county. Nearby jurisdictions in the corpus, including the City of Ammon and Twin Falls County, have each amended or otherwise published their own version of that table; Bonneville County has not, and its own website does not publish a design-criteria document either. This record does not supply figures Bonneville County has not published, and does not borrow a neighboring jurisdiction's numbers -- ask the Planning, Zoning, and Building Department for the design values it actually applies before specifying a roof.

Neither the State of Idaho nor Bonneville County modifies the model rule, and the County says so about itself in its own adopting section. IDAPA 24.39.30.600.03 -- the Idaho Building Code Board's complete list of state amendments to the 2018 International Residential Code, seventeen items, read in full -- contains no amendment to Chapter 9, Roof Assemblies. Bonneville County Code 150.01, Codes Adopted, adopts "the approved editions" of the 2018 International Building Code and the 2018 International Residential Code, Parts I through VI and IX, "as adopted by the state," and states outright: "All amendments made by the state or the State Building Code Board and the State Fire Marshal's office are included" -- meaning the County's own amendment list is empty. The whole of Chapter 150, Building Regulations, was read: it runs to exactly three sections (150.01 Codes Adopted, 150.02 Safety Assessments of Buildings and Structures, 150.99 Penalty), and nothing in it touches roofing, Chapter 9, or any building-code technical provision at all. The base 2018 IRC provisions therefore apply unmodified in unincorporated Bonneville County. Base-code rule, 2018 IRC Section R908.3.1.1 (Roof recover not allowed): a roof recover is not permitted where the existing roof or covering is water-soaked or has deteriorated to the point that it is not an adequate base for additional roofing; where the existing roof covering is slate, clay, cement or asbestos-cement tile; or where the existing roof already has two or more applications of any type of roof covering. One existing layer may be recovered; a second forces a full tear-off. A local Idaho amendment to this rule would be unusually visible: Idaho Code 39-4116(4)(d) allows a city or county to amend this part of the residential code only by ordinance, on a recorded finding that "good cause for building or life safety exists," after a public hearing noticed in the official newspaper with at least thirty days' written notice to the local chapters of the industry bodies listed in Idaho Code 39-4109(5). Bonneville County has taken no such step.

IDAPA 24.39.30.600.03 -- the State of Idaho's complete list of amendments to the 2018 International Residential Code, read in full -- contains no amendment to Chapter 8, Roof-Ceiling Construction, which carries the code's roof sheathing provisions, nor to Chapter 9, Roof Assemblies. Bonneville County Code 150.01, Codes Adopted, adopts the 2018 IRC and states that all amendments to it are the state's, adding none of the County's own; the whole of Chapter 150, Building Regulations -- three sections in total -- was read and none of it touches roofing or roof-covering technical requirements. The base 2018 IRC roof sheathing and decking requirements therefore apply unmodified in unincorporated Bonneville County, along with the shingle manufacturer's printed installation instructions, which the code makes binding. The County has not amended or otherwise published its own version of Table R301.2(1), the climatic and geographic design criteria table that would set a local ground snow load, so no jurisdiction-specific figure for the deck's design load is stated here; see wind design criteria in this record.

6.0% -- the Idaho state rate, with no local add-on. Idaho Code 63-3619 imposes the state sales tax "at the rate of six percent (6%)." Idaho has only two kinds of local sales tax, and neither reaches unincorporated Bonneville County or its principal city: a resort-city local-option tax, which Idaho Code 50-1044 confines to resort cities "with a population not in excess of ten thousand (10,000)," and whose participating-cities list, fetched directly from the Idaho State Tax Commission for this record, does not name Idaho Falls, Ammon or any Bonneville County jurisdiction; and an auditorium-district tax, which the Tax Commission states applies "only for short-term lodging (30 days or less)" and so never reaches roofing work in any event. Idaho counties levy no sales tax of their own, so Bonneville County adds nothing on top of the state rate. HOW A ROOF IS TAXED, which matters more than the rate: the Tax Commission's contractor guidance states that "Idaho sales tax law says contractors are the consumers (end users) of all the goods they use. As a result, they must pay sales tax on all purchases," and names roofers among the contractors it covers. The roofer pays the 6% on materials at the supply house; the homeowner's invoice carries no sales tax line at all, because "a contractor doesn't charge sales tax to the customer," and the Commission adds that "if sales tax is charged on the bill, the customer can refuse to pay it."