Does Colorado's Wildfire Resiliency Code affect my garage door?

Colorado's 2025 Wildfire Resiliency Code (CWRC) is now state law. Jurisdictions in Wildland-Urban Interface (WUI) areas had to adopt it by April 2026 and enforce it by July 2026. If you live in a WUI zone on the Front Range, near the foothills, or in areas of Douglas, Jefferson, Boulder, El Paso, or Larimer counties that border open land, this code may apply to your next building permit. For garage doors specifically, the requirements depend on which fire risk zone your property is in.

What is the Colorado Wildfire Resiliency Code and who must follow it?

The Colorado Wildfire Resiliency Code (CWRC) is a statewide building standard that applies to new construction and additions of 500 square feet or more on properties in designated WUI areas. It does not retroactively require existing homes to upgrade unless a qualifying permit is pulled.

The code was effective July 1, 2025. Local jurisdictions in WUI areas were required to adopt the CWRC by April 2026. Enforcement began July 2026. If your permit is filed after your local jurisdiction adopted the code, the CWRC applies to your project.

Two fire risk zones define how strict the requirements are:

• Orange Zone (High Fire Intensity): The stricter tier. Requires specific ember-resistant construction details including requirements for garage doors.
• Yellow Zone (Moderate Fire Intensity): Lighter requirements focused on roofing, gutters, and vents. No specific garage door provisions apply in Yellow Zones.

To find out which zone your property is in, contact your local building department or visit your county's planning and land use office. The Colorado Division of Fire Prevention and Control (DFPC) maintains the official WUI zone mapping.

What does the CWRC require for garage doors in Orange Zones?

In Orange Zones, the CWRC sets two requirements for garage doors:

1. Ember-resistant sealing. Gaps around the garage door must be sealed with weather-stripping that meets flammability and durability standards. The purpose is to block wind-driven embers from entering the garage. The DFPC publishes a list of tested and approved products on their testing requirements page.

2. Maximum gap size. The gap between the garage door and the door opening cannot exceed 1/8 inch in an Orange Zone. This applies to the top, sides, and bottom of the door. Many older weather-seal installations have gaps far larger than 1/8 inch, particularly at the bottom where concrete floors settle or heave over time.

Three methods meet the Orange Zone garage door requirements:

Compliance method	How it works
Ember-resistant weather-stripping	Tested product that blocks embers, meets DFPC flammability standards
Door overlap onto jambs and headers	Door panel physically overlaps the frame, eliminating the gap mechanically
Metal flashing on jambs and headers	Steel flashing covers the gap at jambs and header so embers cannot enter

Any of these three methods meets the Orange Zone requirement. Your contractor or garage door technician can advise which works best for your door's design.

The most common retrofit approach is ember-resistant weather-stripping. It installs on the existing door frame without major structural changes. For new construction, door overlap is often the cleanest solution because it is built into the door unit itself. Metal flashing is less common on residential garage doors but may be specified by an architect for certain door styles or to match other structural hardening details on the building.

When choosing weather-stripping, look specifically for products that cite DFPC testing approval or reference ASTM E2886 (the standard used to evaluate ember resistance in building components). General-purpose vinyl or foam weather-stripping does not meet the CWRC standard even if it physically seals the gap.

Does the code apply to garage door replacements on existing homes?

Generally no. The CWRC applies to new construction and to additions of 500 square feet or more. A simple garage door replacement on an existing home does not trigger a permit requirement under the CWRC, so it does not automatically require CWRC compliance.

However, there are two situations where a garage door replacement could trigger the code:

1. The replacement is part of a permitted addition or remodel. If you are pulling a building permit for a new addition of 500+ sq ft and replacing the garage door as part of that project, the entire project falls under the CWRC.
2. Your jurisdiction has adopted stricter local requirements. Some Front Range jurisdictions may impose their own wildfire standards on routine replacements in high-risk zones. Check with your local building department before assuming an exemption.

The safest approach is to verify with the Authority Having Jurisdiction (AHJ) for your address before starting any work.

How does this affect a new garage being built in a WUI zone?

If you are building a new attached garage, adding a garage room to an existing structure, or constructing an accessory dwelling unit (ADU) with an attached garage, and your property is in a WUI area, the CWRC applies. The 500 sq ft threshold for additions covers most garage additions.

In an Orange Zone, the entire structure must meet ember-resistant construction requirements. For the garage specifically:

• Door gaps must be sealed to the 1/8-inch standard.
• Weather-stripping must use a tested and approved material.
• The garage door assembly itself must comply with the chosen compliance method (ember seal, overlap, or flashing).

For new garages in Orange Zones, the contractor responsible for the permit must document compliance. An inspection will confirm the door gap is within tolerance before a certificate of occupancy is issued.

What should Front Range homeowners do now?

Whether or not you have a current permit in progress, here are practical steps:

1. Find your zone. Contact your county building department and ask whether your parcel is in a CWRC WUI zone and which tier (Orange or Yellow). You can also look at your county's WUI maps, often published online through the planning department.
2. Inspect your current garage door seals. Use a flashlight from inside the dark garage during daylight. Any visible light around the door frame means the gap exceeds 1/8 inch. Even if you are not under the CWRC, better sealing reduces drafts, pests, and dust.
3. Plan upgrades before pulling a permit. If you expect to add square footage in the next few years, factor CWRC-compliant garage door sealing into your budget. It is cheaper to do it once as part of a permitted project than to retrofit later.
4. Choose tested materials. The DFPC testing requirements page lists ember-resistant products that qualify for CWRC compliance. Not every weather seal qualifies. Look for products that cite DFPC approval or the relevant ASTM testing standard.

How the garage door fits into the broader CWRC structure-hardening plan

Garage doors are one detail in a broader set of requirements. The CWRC applies a "structure hardening" approach, meaning the code targets the parts of a building most likely to ignite from ember exposure. In Orange Zones, those requirements also cover:

• Roofing: Class A fire-rated roofing materials. Rakes and eaves must be enclosed to block ember entry.
• Gutters: Must be covered with non-combustible gutter guards or closed-face gutters that prevent debris and ember accumulation.
• Vents: Attic, crawl space, and eave vents must use 1/16-inch mesh screens or ember-resistant vent covers. This is one of the most common ignition pathways.
• Siding and walls within 5 feet of the structure: Non-combustible or fire-resistant materials in the zone immediately adjacent to the house.
• Decks and porches: Within 10 feet of the structure, combustible decking may require additional treatment or non-combustible covers.

The garage door requirement fits into this broader structure-hardening picture. An ember that enters through a poorly sealed garage door can ignite stored materials inside the garage. The garage then becomes a fire that spreads into the living space through the wall and door assembly. Sealing the garage door is therefore both a CWRC compliance item and a practical fire safety measure.

The Colorado DFPC has published guidance on the CWRC including information on how to determine your zone, what materials qualify, and how to work with local building departments during the transition period. The DFPC website is the primary reference for the most current version of the code and the approved materials list.

G Brothers Garage Doors installs and services garage doors across Denver and the Front Range, including in WUI-adjacent communities in Jefferson, Douglas, Boulder, and Larimer counties. If you are planning a project that may trigger the CWRC, we can advise on door types and seal products that meet the code. Contact us for a free estimate and to confirm what your permit will require.