Stone Coated Steel Roofing Offers Resiliency for Wildfire-Prone Areas
Homeowners in Southern California are only now beginning to rebuild from the devastating wildfires that tore through Pacific Palisades and Altadena in January 2025, leaving thousands of destroyed structures in their wake. Many are choosing to construct their new homes with wildfire-resistant materials like Unified Steel stone coated steel roofing, and others whose homes survived are reroofing with the material in preparation for the future. And for at least one homeowner, stone coated steel is being credited with saving their house and several others on their block.
Stone coated steel roofing offers resiliency for both new construction and retrofits. Both the strength of its material makeup and proven installation methods can help deliver peace of mind amid growing extreme weather threats.
How Stone Coated Steel Roofing Is Made
Unified Steel roofing tiles are made with zinc-aluminum alloy coated steel, which is coated with granules, applied with an acrylic polymer adhesive and covered with a clear acrylic overglaze. The resulting material is extremely durable, benefiting from the structural strength of steel, yet it is still very lightweight at 1.5 pounds per square foot.
Unified Steel comes in a range of profiles and colors, mimicking traditional shake, slate, tile and shingle roofing while delivering the performance benefits of steel. This provides versatility across a range of sloped-roof residential and commercial projects, including single-family, multifamily, churches, military buildings and schools.
Protection From Extremes
Unified Steel stone coated steel roofing systems, when installed with the proper underlayment and attachment processes, provide safety, comfort and protection from some of the most severe climate conditions, including wildfire threats.
Per testing to ASTM E108, stone coated steel roofing can help protect structures from fire spread. Stone coated steel panels can be installed with a specific underlay to achieve a Class A fire rating for the most severe fire-prone areas, providing extra protection from wind-driven embers, which are common during urban firestorms and pose a risk if they come into contact with the home’s roof.
It’s important to note that the Class A fire rating is a systems-based test. Metal roofing is noncombustible, but it doesn’t stand on its own without also considering how it combines with the underlayment and roof deck below. Fire rating levels C, B and A are based on intensity, not time like some other materials. Your local jurisdiction or regional requirements will determine what level of system rating is needed.
Stone Coated Steel Proves Its Worth in California
One homeowner in Altadena witnessed the resilience of stone coated steel first hand during the 2025 wildfires. As the fire spread down a hillside, it destroyed the house next door. Embers blew over and onto the homeowner’s Unified Steel roof; but while the embers scorched the granules, flames didn’t spread. The roof, in combination with stucco and other fire-resistant exterior materials, not only saved the house, but it is credited with preventing the fire from spreading to subsequent houses after it.
Contractor Josh Smith of Covina, Calif.-based JN Davis Roofing Co. recently replaced the damaged roof with new stone coated steel tiles—which was an easy choice for the grateful homeowner.
Smith reports that many homeowners are reroofing with stone coated steel to protect their homes from future fires. “Most people that I talk to now—everyone wants metal roofs,” he says, noting that he and the homeowner also have hosted open houses to educate neighbors about the benefits of a stone-coated steel roof.
Todd Brugma with Western Roofing Systems, based in Anaheim, Calif., is seeing a similar phenomenon, with numerous requests from homeowners looking to upgrade their roofs in the wake of the fires. For one surviving house in the Palisades, the owners replaced a coated wood shake roof with stone coated steel. The system also includes 3” of rigid polyiso insulation underneath along with fire-rated peel-and-stick underlayment.
A homeowner in San Juan Capistrano, farther from last year’s fires but well aware of the ever-present danger, also opted to have Western Roofing replace wood shake with stone coated steel, along with fire-resistant roof deck protection.
“We were replacing a cedar shake roof, and our house has a very French cottage feel to it. We wanted to keep that feel without the fire risk of the shake,” the homeowner says. “Our new roof is gorgeous and we sleep better at night knowing we have some extra protection from fire.”
Steve Szalwinski, a contractor with Western Roofing, notes that, due to earthquakes, replacing a lightweight shake roof with stone coated steel is often an ideal option versus heavier tile that the roof system may not have been designed to hold. In addition, “it’s completely walkable, so you don’t have breakage,” he says. “Plus, it’s energy efficient for our hot summers—and it looks nice.”
Energy Savings Potential
Indeed, in addition to the resiliency benefits during fire events, stone coated steel roofing may also be used as part of a complete Cool Roof System to reduce the structure’s energy consumption and provide cost savings, another issue of increasing importance as temperatures continue to rise.
The Cool Roof System combines the stone coated steel roofing with a high-performance underlayment, elevated batten system and a continuous ridge vent. This system allows warm air to rise and exit the roof system, and the continuous airflow across the roof deck helps create a cooler attic space and living area inside.
Protection in Any Weather
Along with fire protection, stone coated steel roofing stands up to a range of weather extremes. When fastened properly, it can withstand Category 5 hurricane-force winds and meet Coastal Florida’s performance for High Velocity Hurricane Zone (HVHZ), including Miami-Dade Approval. Plus, it carries an Underwriters Laboratory (UL) Class 4 Impact rating and the Factory Mutual (FM) Very Severe Hail (VSH) impact-resistance classification.
With resiliency and durability top of mind not just in California but across the country, the roof is the home’s first line of defense. Homeowners and pros are prioritizing materials like stone coated steel to bring reassurance while protecting their investment well into the future.
Ready to learn more? Explore Unified Steel's array of resilient roofing options here.
