Permitting Authorities / St. Charles County, Missouri - Division of Building and Code Enforcement
Do you need a permit to replace a roof in St. Charles County, MO?
Adopted code
St. Charles County, Missouri - Division of Building and Code Enforcement
Yes — a permit is required to replace a roof in St. Charles County, MO, issued by St. Charles County, Missouri - Division of Building and Code Enforcement. Section R105.1 (unamended base 2021 IRC text, confirmed via the county's own "Building Without a Permit" page) requires a permit for work to "construct, enlarge, alter, repair, move, demolish, or change the occupancy of a building or structure." Section R105.2 (Work exempt from permits), as restated in the county's own residential code amendment document, lists 12 specific categories of exempt building work (accessory structures under 200 sq ft, fences, retaining walls under 4 ft, water tanks, sidewalks/driveways, finish work, small swimming pools, playground equipment, small awnings, small decks, flag poles, and replacement of 3 or fewer doors/windows) -- roofing/re-roofing is NOT among the enumerated exemptions, so a roof replacement or repair falls under the general permit requirement of R105.1. Note that this authority covers only part of the county: "The St. Charles County Division of Building and Code Enforcement issues permits in unincorporated St. Charles County and cities in which we contract." The county's Property Maintenance Code amendments similarly describe that code as applying "to properties in the unincorporated part of St. Charles County and in municipalities that adopt this code and contract with St. Charles County for its enforcement." The county's own pages do not name which specific cities currently hold such contracts; a Permit Lookup Tool is referenced for determining which authority governs a given parcel.
Jurisdiction
St. Charles County, Missouri
Contact
- url: https://www.sccmo.org/1992/Building-Permit-Information
- phone: 636-949-7345
- email: [email protected]
Roofing permit required
Required
Contractor registration required
Not required
Registration details
- license: St. Charles County's Contractor Licensing and Renewals page states: "Electricians, plumbers, mechanical (HVAC) contractors, pool installers, drainlayers, third party inspectors, and blasters are required to have a license through the St. Charles County Building and Code Enforcement Division before doing any work in the county that requires a permit." General/roofing contractors are not named as a licensed trade category on this page.
Permit process note
Section R105.1 (unamended base 2021 IRC text, confirmed via the county's own "Building Without a Permit" page) requires a permit for work to "construct, enlarge, alter, repair, move, demolish, or change the occupancy of a building or structure." Section R105.2 (Work exempt from permits), as restated in the county's own residential code amendment document, lists 12 specific categories of exempt building work (accessory structures under 200 sq ft, fences, retaining walls under 4 ft, water tanks, sidewalks/driveways, finish work, small swimming pools, playground equipment, small awnings, small decks, flag poles, and replacement of 3 or fewer doors/windows) -- roofing/re-roofing is NOT among the enumerated exemptions, so a roof replacement or repair falls under the general permit requirement of R105.1. Note that this authority covers only part of the county: "The St. Charles County Division of Building and Code Enforcement issues permits in unincorporated St. Charles County and cities in which we contract." The county's Property Maintenance Code amendments similarly describe that code as applying "to properties in the unincorporated part of St. Charles County and in municipalities that adopt this code and contract with St. Charles County for its enforcement." The county's own pages do not name which specific cities currently hold such contracts; a Permit Lookup Tool is referenced for determining which authority governs a given parcel.
Adopted code
St. Charles County Ordinance amending OSCCMo Chapter 500, Article III, Section 500.150 ("Adoption of Residential Code For One and Two-family Dwellings"): "St. Charles County hereby adopts the 2021 St. Charles County Residential Code for One- and Two-family Dwellings" (i.e., the 2021 International Residential Code as locally amended), applicable per R101.1 to "the Residential Code for One- and Two-family Dwellings of ... St. Charles County, Missouri." The county's Building and Construction Codes page also lists a companion 2021 I-Code suite (2021 IBC, 2021 IEBC, 2021 IMC, 2021 IFGC, 2021 IPC, 2021 IPSDC, 2021 IECC, 2021 IFC, 2021 ISPSC) plus the 2020 NEC, packaged as the county's "Custom Local Building Codes (CLBC)."
Drip edge
Required — Sec. R905.2.8.5 Drip Edge (2021 IRC, restated in the county's own residential code amendment document): "A drip edge shall be provided at eaves and rake edges of shingle roofs. Adjacent segments of drip edge shall be overlapped not less than 2 inches (51 mm). Drip edges shall extend not less than 1/4 inch (6.4 mm) below the roof sheathing and extend up back onto the roof deck not less than 2 inches (51 mm). Drip edges shall be mechanically fastened to the roof deck at not more than 12 inches (305 mm) o.c. with fasteners as specified in Section R905.2.5." The county ADDED a local exception (bold text in the amendment document): "Exception: Unless the drip edge is specifically required by the manufacturer's installation instructions, metal wrapped fascia extending 1 inch under the roof covering with the underlayment installed over it shall be deemed to meet the requirements of this section."
Ice & water shield
Not required — 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.
Wind design criteria
Table R301.2 (Climatic and Geographic Design Criteria) as filled in by the county's residential code amendment: "Wind Design -- Speed (mph): 107(48). Topographic effects: NO. Special wind region: NO. Windborne debris zone: NO." (Ground snow load 20 psf; Seismic Design Category C.)
Sales & use tax
Combined general sales tax rate for unincorporated St. Charles County is 5.9500% (Missouri DOR jurisdiction code 00000-183-000: 4.225% state + county), per the DOR's statewide Sales/Use Tax Rate Table for July-Sept 2026 (run date 5/22/2026). This is the flat unincorporated-county rate; it does not include any city, fire-district, or CID/TDD add-ons, which apply only within incorporated areas or special districts. Incorporated cities within St. Charles County (the City of St. Charles, O'Fallon, St. Peters, Wentzville, Lake St. Louis, St. Ann-area zones, etc.) each carry their own higher combined rates. Missouri's own Contractors Tax Matrix (DOR Audit Services, Industry Guidance, eff. 10-24-2022, https://dor.mo.gov/taxation/business/documents/Contractors_000.pdf) treats a roofing contractor as the final consumer of materials incorporated into real property: "Contractor sales of tangible personal property where title passed to the customer after installation" is listed Exempt, while "Tangible personal property to be sold as an attachment to real property" is listed Taxable -- meaning the contractor owes sales/use tax on shingles, underlayment, etc. at the point of purchase from the supplier, and does not separately charge the homeowner sales tax on the installed roof or on labor. No Missouri jurisdiction covered here collects a construction use tax at building-permit issuance; the DOR's own Sales/Use Tax page (https://dor.mo.gov/taxation/business/tax-types/sales-use/) describes local use tax as a self-reported obligation.
The permitting authority for unincorporated St. Charles County, Missouri, and for municipalities within the county that contract with the county for building inspection services. The Division of Building & Code Enforcement, within the Department of Community Development, issues building permits under the county's adopted 2021 Residential Code for One- and Two-Family Dwellings (amended 2021 IRC). County's own building-permitting page states: "The St. Charles County Division of Building and Code Enforcement issues permits in unincorporated St. Charles County and cities in which we contract."
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