As our population increases and urban development pushes further into wilderness areas, wildfires have become a growing threat to communities in the United States. Fires have always been a natural part of forest ecosystems, but rapidly changing climate dynamics are contributing to longer fire seasons and more extreme conditions. While most wildfires have occurred in the Western U.S., there are growing wildfire threats in the Midwest, East and South.

The impacts affect not just our wildlands, but the residential communities adjacent to them, known as the Wildland-Urban Interface (WUI). According to the Insurance Institute for Business and Home Safety (IBHS) roughly 45 million residential buildings in the U.S. are now located in WUI areas that are at high risk for wildfires.

Evolving Construction Practices in High-Risk Zones

To address the increasingly widespread occurrence of wildfires close to home, new building standards and design practices are being developed and put into place in jurisdictions across the country.

California and Utah, impacted by dramatic increases in wildfire activity, are the only two states with comprehensive WUI requirements embedded in their state building and fire codes. California went a step further by consolidating those requirements in the California Wildland-Urban Interface Code (CWUIC), which took effect January 1, 2026.

The CWUIC, which is modeled on the International Wildland-Urban Interface Code (IWUIC), establishes minimum standards for building materials, construction methods and mitigation strategies in areas vulnerable to wildfires.

The Importance of Class A fire rated roofing

There are three main ways that wildfire conditions lead to building ignition:

• Wind-blown Embers - responsible for 60-90% of residential fires in WUI zones. Strong winds can cause embers to travel more than a mile ahead of a wildfire.
• Direct Flames - from fire itself or from combustible materials near homes
• Radiant Heat - extreme heat exacerbated by nearby fires can cause some building materials to combust

Residential roofs are particularly vulnerable to fires that are spread by wind-blown embers. Due to their large exposed surface areas, gutters, vents, and other features where embers can easily collect, they have become a major focus for wildfire-resilient design strategies.

According to Chris Buhowski, GAF Senior Product Manager, IWUIC standards are having a greater influence on residential roofing design and construction: "It hit the market in a big way within the last couple of years and is expanding pretty rapidly. In a lot of jurisdictions, it's becoming a requirement for any reroof or new construction."

In severe fire zones, WUI standards require roofing to have a Class A roofing fire rating, tested in accordance with ASTM E108 or ANSI/UL790. A roofing assembly (as opposed to just a single material) includes decking, underlayments, fasteners and edge details, as well as the roof covering.

The International Code Council (ICC) classifies roof assemblies into three tiers:

‍Class A: Effective against severe fire exposure. Required for high-risk buildings, urban settings or structures less than 3 feet from property lines.

Class A roofs must be able to:

• Withstand flame exposure without igniting
• Resist the spread of flames across the roof surface
• Prevent the production of hot, flying pieces of burning material (called “brands”) that could ignite other nearby structures

Class B: Effective against moderate fire exposure. Acceptable for most general construction types.

‍Class C: Effective against light fire exposure. Minimum rating typically required for code compliance of structures.

The majority of residential roofs are asphalt shingles, some of which are manufactured to carry a Class A roofing fire rating. Tile and metal roofs, even though they may be made of materials that are naturally fire-resistant, have certain characteristics – like elevated profiles, gaps, or heat-conductive surfaces – that make it more challenging to meet Class A requirements.

The Role of Fire-Resistant Leak Barriers

FT Solutions™ Specialty FR Leak Barrier , a peel-and-stick, single sheet leak barrier, plays an important dual role: it provides a layer of protection that helps certain metal and tile roofing assemblies earn a Class A roofing fire rating, while also helping to protect against leaks caused by wind-driven rain.

Paul Dellanno, Senior Brand Manager for FT Solutions™ , elaborates on the advantages of this new product:

The Specialty FR Leak Barrier is one of our premium products that focuses on metal and tile roofing systems. It achieves an ASTM E108 Class A roofing fire rating when used with select metal panels, asphalt roof shingles, and clay and concrete tiles.* So it can be used to comply with certain WUI building code requirements.**

Its other outstanding characteristics include:

• Heat Resistance: While metal and tile panels are non-combustible materials, their high thermal conductivity means the complete roofing assembly needs an underlayment with high temperature resistance. This product provides high temperature resistance up to 250°F to help stand up to the heat under metal roofing and clay and concrete tiles.***
• UV Resistance: Provides 180 days of UV resistance for extended construction schedules.****
• Waterproofing Protection: It meets or exceeds ASTM D1970 nail sealing requirements to help protect against water intrusion.
• Installation Ease: Many underlayments are mechanically attached. One of the primary advantages of the Specialty FR Leak Barrier is its labor-saving" peel-and-stick" installation capability.
• Excellent Traction: Like all FT Solutions™ leak barriers and underlayments, it features patented GripSpot™ technology for enhanced walkability.

Covering All the Bases for Long-Term Resiliency

In addition to complying with certain WUI building code requirements,** the FT Solutions™ Specialty FR Leak Barrier also meets certain FORTIFIED™ Roof requirements. ***** The FORTIFIED™ program was developed by IBHS as a voluntary roofing construction standard to help protect homes against severe storms. FORTIFED™ Roof requires the use of certain approved materials and methods for a new or replacement roof, followed by third party verification and official certification. Earning a FORTIFIED™ Roof designation can help unlock insurance discounts, state grants, and a higher home resale value.

IBHS has also pioneered a new program called Wildfire Prepared Home, which is available in 14 states so far. Similar in structure to the FORTIFIED™ program, it helps reduce wildfire risk to homes by requiring the use of fire-resistant materials and specific mitigation actions. It also requires third party verification and provides certification for homes that meet its standards. Because Wildfire Prepared Home requires a Class A fire-rated roof assembly, Buhowski emphasizes that FT Solutions' Specialty FR Leak Barrier serves as an essential component designed to help the roof system achieve this benchmark.

FT Solutions™ (formerly FT Synthetics™), a GAF brand, is a fully integrated manufacturer of leak barriers, underlayments, and interior surface protection for steep-slope roofing. Designed for metal, tile, and a variety of roof surfaces, FT Solutions products feature patented GripSpot™ technology for enhanced foot traction and are backed by GAF's technical support network. Learn more at www.ftsolutionsroof.com.