What is the Best Type of Roof for Fire?

Historically, concerns about fire-resistant roofing were mostly limited to residents of the Western United States. States like California, Arizona, Nevada, and Colorado frequently battled wildfires, particularly in late summer and fall.

Today, however, the wildfire threat is more significant and widespread due to several factors:

Longer Fire Seasons: The fire season in the western U.S. has extended and can now be a year-round concern.

Expanded Risk Zones: High-risk areas have grown to include parts of the Northeast.

New Vulnerable Regions: Previously low-risk areas in Canada have experienced severe fires.

More Intense Fires: Wildfires are becoming larger and more powerful, even capable of altering local weather patterns.

Future Projections: Experts predict an increase in fire frequency due to drought and rising temperatures.

Recent, highly destructive wildfires have highlighted this new reality. In many cases, homes with the right design choices-especially roofing materials-survived while neighboring houses were lost. Metal roofs, in particular, have proven effective at stopping fire spread.

The next section explores what makes a roofing system fire-resistant and why material choice is so important.

Combustible vs. Non-Combustible Materials
As many firefighters will attest, the primary danger to a home isn't always the main fire front; it's often the wind-blown embers that can travel miles ahead. This is why starting with a non-combustible roofing material is your best defense.

"Non-combustible materials are absolutely a factor when assessing if an insurer is willing to cover the risk they are underwriting," explains Christen Losey-Gregg, a member of the CPIRA and the Private Risk Management Association. "As fire season persists, it is becoming increasingly difficult to get favorable coverage and deductibles for these risks."

Non-combustible materials include metal, tile, and concrete. These will not ignite and spread flames.
Combustible materials include wood shakes and some asphalt shingles. Even Class A asphalt shingles (see below) are made from asphalt, a petroleum product that can eventually burn under extreme conditions.

All roofing products are tested and classified for fire resistance by Underwriters Laboratories (UL), an independent safety science company. Products are rated as follows:

Class A: The highest rating, effective against severe fire exposure. These products offer the best protection against flame penetration and surface spread without additional chemical treatment. They can withstand direct flame exposure without igniting.

Class B: A moderate fire-resistant rating. These products are typically treated with fire-retardant chemicals and offer better protection than Class C, but may still ignite under prolonged, extreme heat.

Class C: Offers light fire protection. They resist ignition better than unrated materials but will eventually catch fire.

Unrated: Materials that do not meet the minimum testing standards of UL 790 (ASTM E 108).

It's important to choose a material with a Class A rating for the best protection.

While the roofing material itself is the critical first line of defense, true fire resistance comes from the entire roofing assembly. This system includes:

The Underlayment: The protective layer directly beneath the roofing material.

The Decking: The wooden, OSB, or metal surface that provides the roof's structure.

The Insulation: Helps regulate temperature but should also be non-combustible.

Flashing and Ventilation Components: These seal the roof's edges and promote airflow. They must be correctly installed to prevent embers from entering gaps or seams.

The first three components can be treated or chosen for fire resistance. Flashing and vents must be properly installed to create a continuous, ember-resistant barrier.

Beyond the Roof: Additional Home Hardening Tips
Installing a fire-resistant roofing system is a vital first step, but it's not the only one. Other measures, often called "home hardening," can signific