Unincorporated Boulder County is one of only two Colorado jurisdictions in our survey that mandates hail-resistant roofing: county building-code amendments require asphalt shingles to be Class 4 impact resistant per UL 2218. Class A fire-rated coverings are required in all Wildfire Zones, and a permit is required for new or replacement roof coverings.

Hail mandate	Asphalt shingles shall be Class 4 impact resistant, tested in accordance with UL 2218 — Boulder County Building Code amendment to IBC 1504.8.1 / IRC R905.2.4.2. The legal minimum, not an upgrade.
Fire	Class A roof covering or roof assembly is required in all Wildfire Zones; exterior materials are regulated in Wildfire Zone 1.
Permit & inspection	Permit required for new or replacement roof coverings (IRC R908 / IBC 1512). Gutters removed for the reroof must be reinstalled before inspection.
Ice barrier	Not required unless there is evidence of previous ice-dam damage or clear potential for it — looser than neighboring counties.

Details to confirm with the county

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

• City of Boulder, Longmont, and other incorporated cities permit through their own building departments — their rules differ.

Verified July 2026 · Source: Boulder County — Building FAQs (roofing)