As fire season heats up in the West and the Fourth of July holiday’s fireworks displays are scheduled from coast to coast, now is one of the riskiest times for roof fires.
Fortunately, many common roofing materials are fireproof. In fact, many municipal building codes require fireproof or fire-resistant materials to be used on roofs, especially in fire-prone areas.
How Shingles Are Rated
Shingles are classified by their fire resistance, with Class A shingles being the most fireproof. Class A shingles can withstand a fire burning through a wooden structure for up to two hours. Class A shingles are the most common roofing materials. They generally are also the most affordable.
Most fiberglass shingles are designated as Class A, bu organic shingles — such as those made from treated wood — are Class C or the least fire resistant.
Fireproof Roofs for High-Risk Areas
But in places where fire is a genuine risk, roofing materials that are more fireproof or fire resistant are often used. These include concrete, clay, slate and metal.
Metal roofing materials are frequently used in areas where corrosion is an issue, such as near salty oceans. Many metals used in roofing have the dual benefit of being corrosive resistant and fireproof.
There also are metal rooftop coatings and insulation that can be used to improve the fire protection of a roof.
The Strength of Slate
Slate is another type of roofing material that won’t burn. It’s also essentially indestructible. But slate is expensive and requires specialized installation. And it’s heavy, so before it can be applied to a roof, a qualified engineer needs to do a load bearing assessment of your home to make sure it can handle the considerable weight.
Concrete and clay are widely used in industrial and commercial roofs. Fireproof and durable, concrete and clay roofing tiles provide structural support. But like slate, they are substantially heavier than other roofing materials.