Unincorporated Arapahoe County requires a re-roof permit for any full roof replacement, and for repairs once the affected area passes 100 square feet across any slope or combination of slopes. The county adopted the 2021 International Codes effective April 1, 2022, publishes a residential reroofing guide, and runs a third-party roof inspection option.

When a permit is required	Full roof replacements always; repairs and partial replacements once the total repair area on any roof or combination of slopes exceeds 100 square feet.
Code edition	2021 International Building Code / International Residential Code, adopted effective April 1, 2022.
Inspections	Mandatory inspections verify code compliance; the county also operates a third-party roof inspection pathway — ask which applies to your job.
Contact	Arapahoe County Building Division, (720) 874-6600. Incorporated cities (Aurora, Centennial, Littleton…) permit through their own building departments.

Details to confirm with the county

We couldn't confirm the following from Arapahoe County's official pages. Check these with the county before you rely on them:

• City-by-city rules inside incorporated Arapahoe municipalities — each city's building department governs its own reroofs.

Verified July 2026 · Source: Arapahoe County — Residential Permit Requirements / Reroofing Guide (2024)