Colorado wildfire roof code FAQ: common homeowner questions

What is the Colorado Wildfire Resiliency Code?

The CWRC is a statewide minimum building code adopted July 1, 2025, through 8 CCR 1507-39. It is based on the 2024 International Wildland-Urban Interface Code with Colorado amendments. It is not retroactive, it does not apply statewide, and local jurisdictions choose whether, how, and when to adopt it.

Who does the code actually apply to?

It applies to homes inside mapped WUI areas where the local city, town, county or fire district adopted a code meeting or exceeding the state minimum. Two homes on the same street can fall into different jurisdictions and therefore different rules. The only way to know for certain is to confirm with the building department that issues your permit.

What triggers the 25% reroof rule?

In a mapped WUI area, any of these triggers the whole roof covering to meet new-construction requirements:

• Replacing the roof covering, even the entire roof.
• Replacing 25% or more of the total roof surface area in any 12-month period.
• Doing work that effectively replaces the covering, such as a large repair that removes the existing roof covering.

Does a small repair trigger the whole-roof requirement?

Not if it stays under 25% of the roof surface and does not replace the covering. Once the work crosses the 25% threshold, the entire covering must meet the Class A, ember-space, vent and valley-flashing requirements as if it were new construction.

What does Class A roofing mean?

Class A is the highest fire rating under ASTM E108 and UL 790. A Class A roof survived a severe fire exposure test with flame spread of no more than 6 feet, no fire penetration through the deck, and no flying brands. The code requires Class A in mapped WUI areas when triggering work occurs.

Are asphalt shingles automatically Class A?

Virtually all modern fiberglass-mat architectural asphalt shingles carry a stand-alone Class A rating, so most recent asphalt roofs already qualify on the covering. Compliance still depends on the installed assembly, underlayment, vents and flashing, so verify the specific product listing rather than assuming.

Are metal roofs automatically Class A?

No. Metal roofing is usually Class A by assembly, not stand-alone. It needs the listed fire-rated underlayment or barrier from its test report. A steel panel over a bare wood deck with ordinary felt can rate as low as Class C because heat conducts through the metal.

What are ember-resistant vents?

Ember-resistant vents are designed to stop wind-blown embers from entering attics, enclosed rafter spaces and underfloor areas. The code accepts two paths: vents listed to ASTM E2886, or noncombustible corrosion-resistant mesh with openings no larger than 1/8 inch.

Do I need new vents when I reroof?

In a mapped WUI area where the code applies, yes. When triggering reroof work occurs, the vents must meet the ember-resistant standard. This is often the most overlooked part of a low bid, because standard vents cost a few dollars and listed ember-resistant vents cost more. We specify them as standard scope, not an upsell.

Can I keep vinyl gutters in a WUI area?

No. The code requires gutters and downspouts to be noncombustible, which excludes vinyl and plastic gutters in mapped areas where the code applies. Metal gutters are required, and keeping them clear of debris is strong practice even where the code does not apply.

Will a Class A roof lower my insurance premium?

Documented mitigation, including a Class A roof and ember-resistant vents, improves insurability and may reduce your premium, but Colorado has not set fixed statewide discount percentages. Under HB25-1182, insurers must disclose your wildfire risk score and either model your mitigation or offer discounts for documented mitigation. The bigger benefit in high-risk areas is often keeping coverage at all.

Is there a Colorado tax credit for wildfire mitigation?

Yes. C.R.S. 39-22-543 offers a wildfire mitigation income tax credit. For tax year 2025 onward it is 100% of costs up to a $1,000 annual cap, subject to an income eligibility limit. You must own the land and keep receipts. Confirm your specific eligibility with the Colorado Department of Revenue or your tax preparer.

How do I check if my home is in a WUI area?

Start with the Colorado Wildfire Risk Public Viewer and the 2025 CWRC map for a general read, then call your county or town building department to confirm which map they adopted and what classification your parcel carries. The local adopted map is what governs your permit.

What should I ask a roofer before signing a contract?

Ask for four things in writing:

• Whether the project crosses the 25% threshold and triggers the whole-roof requirement.
• The exact Class A product and whether the rating is stand-alone or by assembly.
• The vent, gutter, valley flashing and underlayment details that make the assembly compliant.
• Manufacturer listing documentation and permit/inspection records for your insurance file.

Does the code apply to every roof in Colorado?

No. The CWRC applies only in mapped WUI areas where the local jurisdiction adopted it. Enforcement is entirely local. A home outside a mapped area, or in a jurisdiction that declined to adopt, is not covered by the code's building requirements.