Colorado WUI Roof Code 2025: Class A Compliance Checklist for Roofers

Class A fire rating in a Colorado WUI parcel is an assembly rating, not a shingle rating, and most jurisdictions are enforcing it starting July 1, 2025, but adoption is not uniform. Call your local AHJ before you write a bid. Covering, underlayment, deck, flashing, and roof vents all have to work together as a single tested assembly. Confirm the exact scope, the mapped WUI boundary, and whether re-roofs get pulled into scope at a percentage-of-area threshold. Do not assume the county next door has the same rule.

This is a working checklist for roofing contractors bidding, permitting, or tearing off in a Colorado WUI zone. It stays in job-site terms: squares, pitch, tear-off, waste factor, and what this actually does to your estimate and your crew schedule.

What Class A actually covers on the roof

Class A fire classification is an assembly rating, not a shingle rating. A shingle tested as Class A over a specific underlayment and deck configuration does not automatically carry that rating over a different deck or a different underlayment. If your spec sheet lists a tested assembly, you need to match every layer in that assembly, not swap in whatever underlayment roll is on the truck.

• Roof covering (shingle, tile, metal panel, or treated shake where a specific tested exception exists)
• Underlayment type and layer count as listed in the tested assembly
• Deck material and thickness
• Flashing at valleys, chimneys, and penetrations
• Roof and attic vents, since open vent gaps are a known ember entry point on wildfire-exposed homes

Untreated cedar shake and shingle roofs are effectively off the table in mapped WUI zones unless the local AHJ has confirmed a specific fire-retardant-treated assembly in writing for that jurisdiction. Do not tell a homeowner "cedar should be fine" without that confirmation in hand. That is how a contractor ends up re-doing a roof after a failed inspection.

Building the compliance checklist before you bid

Run this before you put a number in front of a homeowner or insurance adjuster:

• Pull the parcel address and confirm it sits inside a mapped WUI boundary with the local planning or building department
• Confirm the jurisdiction's re-roof threshold, some counties treat any re-roof over a set percentage of roof area as new construction for code purposes
• Get the tested assembly spec sheet from your manufacturer rep, not a generic product page, and match it layer by layer
• Check whether the AHJ requires a pre-installation submittal or just a final inspection sign-off
• Document existing deck condition with photos before tear-off, since deck replacement changes the assembly and may require a new compliance path

If you are still working off a paper measurement or a rough walk-around, get a satellite or drone measurement report before you finalize pitch, squares, and linear footage for ridge, hip, and valley. RoofWright pulls those measurements straight into the estimate so you are pricing the actual roof geometry, not a guess, before you commit to a compliant assembly cost.

The cedar shake substitution conversation

Homeowners in mountain and foothill communities often want the cedar look they had before, or the look their neighbor has. Have this conversation early, before you measure the roof:

• Untreated cedar shake or shingle is presumptively non-compliant in a mapped WUI parcel
• Fire-retardant-treated shake products exist with Class A listings, but the listing is tied to a specific manufacturer assembly, so you cannot mix brands or skip the specified underlayment
• Composite and synthetic shake-profile products carry Class A ratings without the treatment maintenance concerns of treated wood, and many homeowners accept the look once they see samples
• Metal shake-profile panels are another Class A path worth pricing alongside composite, especially in high wind or hail exposure areas along the Front Range

Price all three options side by side in the proposal. Homeowners make a faster decision when they see the cedar-look alternatives next to the treated-cedar number instead of hearing "cedar is a problem" with no path forward.

How WUI compliance changes the estimate

Compliance does not just change the material line. It touches labor, waste factor, and contingency pricing.

• Pitch-driven labor. Steep-slope roofs (generally above 7/12) already carry a labor premium under NRCA guidance for fall protection and crew productivity. A compliant assembly with heavier underlayment or an added layer adds handling time on top of that, so adjust your steep-slope day rate before you quote.
• Tear-off and layer count. A single-layer tear-off and a two-layer tear-off are different jobs. If the existing roof has a second layer under the cedar or shingle, factor extra dumpster capacity and tear-off labor hours, and confirm the deck is sound enough to skip full decking replacement.
• Waste factor. Complex rooflines with lots of hip, valley, and ridge linear footage push your waste factor up, especially with cut-heavy synthetic shake profiles. Measure ridge, hip, and valley separately rather than eyeballing a flat percentage across the whole roof.
• Decking replacement contingency. Build a per-square contingency line for deck replacement into every WUI bid. Once you're into tear-off, plywood or OSB that looked sound from the ground sometimes isn't, and a compliant assembly spec often calls for a specific deck thickness you may not currently have.
• Material branch availability. Treated shake, specific Class A underlayment rolls, and composite shake-profile panels are not always sitting on the shelf at your local branch. Call and confirm lead time on the exact SKU in the tested assembly before you commit to a start date, not after you've torn off the old roof.

Storm season material reality: soft-metal vs laminate

During storm season, insurance-driven demand pulls material fast, and branches run short on specific SKUs first. If a hailstorm rolls through the Front Range in the same season WUI enforcement is active, expect two pressure points at once: adjusters pushing volume through fast, and Class A-listed materials moving slower off the shelf than standard laminate.

Soft-metal panels (standing seam and some shake-profile metal) generally hold up better against hail impact and carry strong manufacturer wind warranties when installed to spec, but lead times can run longer during a busy storm cycle. Standard laminate shingles are usually more available but require careful matching to the tested WUI assembly, since not every laminate line has a Class A listing tied to your local underlayment spec. Confirm availability before you promise a homeowner or adjuster a start date.

Insurance reroofs vs retail reroofs under WUI rules

An insurance-driven reroof after storm damage and a retail reroof a homeowner initiates on their own timeline hit WUI compliance differently.

• On an insurance job, the adjuster's scope sheet often prices standard materials. If the WUI-compliant assembly costs more than the adjuster's line item, you need a documented supplement request before tear-off, not after.
• On a retail reroof, you control the proposal from the start, so build the compliant assembly cost in from square one and avoid the mid-job supplement conversation entirely.
• Either way, keep photos of the existing assembly, the tear-off, and the new assembly layer by layer. If an adjuster or inspector questions the rating later, you want proof the job matched the tested spec.

Pricing steep-slope crews for WUI jobs

Steep-slope crews already price differently than a standard-pitch crew, and WUI jobs add handling time for heavier underlayment and, on some jobs, treated shake. Confirm pitch with a pitch gauge before you set the day rate, not from a drone photo alone, since roof planes can vary across additions and dormers on the same house. Walk the ridge and valley lines with a measuring wheel or confirm your drone/satellite report's linear footage against a ground check on at least one plane, especially on complex rooflines where a measurement error changes your crew day count.

Get the pitch and linear footage right before you set the day rate, not after the crew is on the roof. A wrong pitch call on one plane is the difference between a profitable day rate and a crew that runs long on labor you already quoted.

Documentation and inspection prep

Keep a job file for every WUI project that includes the manufacturer's tested assembly spec sheet, photos of each layer during install, the permit and any AHJ correspondence confirming jurisdiction rules, and the final inspection sign-off. If enforcement tightens over the next couple of building seasons, as most contractors expect it will, the jobs with clean documentation are the ones that don't get reopened.

Frequently asked questions

Do I need a Class A rating on a repair, or only a full reroof?

It depends on the jurisdiction. Many local ordinances extend Class A requirements to re-roofs that exceed a set percentage of total roof area, not just new construction or full tear-offs. Confirm the exact threshold with the local building department before you scope a repair as "just a patch."

Can I still install untreated cedar shake in a Colorado WUI zone?

Generally no. Untreated cedar shake and shingle are presumptively non-compliant in mapped WUI parcels unless the local AHJ has confirmed a specific fire-retardant-treated assembly in writing. Get that confirmation before you bid the job, not after.

Does a Class A shingle stay Class A over any underlayment?

No. Class A is an assembly rating. The same shingle can lose its rating if installed over a different underlayment or deck than the one listed in the tested assembly. Match the manufacturer's spec sheet layer by layer.

How do I price the extra risk on a WUI tear-off?

Build a per-square contingency for deck replacement, account for layer count on tear-off (single vs double layer changes dumpster and labor needs), and confirm material lead time at your branch before you set a start date. Steep-slope pitch adds its own labor premium on top of that.

Does homeowners insurance affect WUI roofing decisions?

Some carriers in wildfire-exposed areas are paying closer attention to roof covering type when underwriting or renewing policies. That is a conversation between the homeowner and their carrier, but it is worth mentioning during the proposal since it can affect which material option a homeowner prefers.

What's the fastest way to get accurate measurements for a WUI bid?

Pull a drone or satellite measurement report for squares, pitch, and ridge/hip/valley linear footage, then verify pitch with a pitch gauge and spot-check one plane with a measuring wheel. That report becomes the backbone of a compliant bid. If you want it built straight into the estimate rather than re-typed from a PDF, RoofWright is built for exactly that handoff.