What Roofing Materials are Most Fire Resistant?

This is a broad question with a not-so-simple answer. Manufacturers periodically explore the creation of new roofing materials to suit a variety of purposes. They then go through a testing process. After the devastating Northern California wildfires of 2017 and 2018, homeowners are demanding more information about fire resistant roofing materials.


How Do You Choose the Best Fire Resistant Roofing Material?

Thousands of homes need to be rebuilt from the ground up, while other homeowners face partial roofing repairs from fire or storm damages. Other homeowners may simple discover it is time to replace an old, worn out roof.  So where do you start to get trusted information about the best roofing material for your home’s location?

In California, roofing materials are rated for different code-compliant standards. The University of California provides a Homeowner’s Wildfire Mitigation Guide with a special section on roof coverings in simple to understand language. Basically, roofing materials are rated as Class A, B or C.

Anyone concerned about fire resistant roofing materials will choose a Class A rated material.

In fact, if you are building, rebuilding, repairing or replacing a roof in a high fire-danger area, you will be required to use A rated materials. Class A rated roofing materials have been tested and proven to be the most fire resistant.

Things get a bit more complicated when you consider whether the material is a stand-alone fire Class A or what is called an assembly-rated Class A. As you might have guessed, the stand-alone Class A, by itself, is fire resistant. An assembly-rated Class A requires an additional, underlying layer, or layers, to ensure the fire resistant rating.

Class A Fire Resistant Materials

Class A stand-alone:

  • Composite asphalt glass fiber shingles
  • Concrete tiles
  • Clay tiles
  • Slate

Class A assembly-rated:

  • Metal roofs (with underlying Type 72 capsheet material)
  • Select (not all) recycled rubber and plastic shingles
  • Fire-retardant treated wooden shake shingles (with underlying gypsum­glass fiber panel)

A fire-retardant treated wooden shake shingle, is a stand-alone, without the underlying gypsum­glass fiber panel and receives a rating of Class B.

Working with a reputable roofing company can help to ensure that in the rush to rebuild, repair or reroof, you are not fooled into thinking you are getting protection that does not exist without added materials. Other things can impact whether your roof is fire safe.

What Else Can You Do?

Unfortunately, even Class A roof materials cannot protect you completely from fire. You’ll want to consider at least two more elements to a safe roof:

  1. Edge-of-roof issues;
  2. Vegetation surrounding your home.

Edge-of-roof issues means you will want to check the areas where your roof is adjacent to (up against) a higher portion of your home, like an upstairs addition, or dormer window. Debris can collect in these areas. Dry leaves, pine needles or small tree branches can ignite and provide added fuel to an area of your roof, close to a wall with siding that may not be fire resistant, diminishing the fire safety of your home.

Screening to keep small birds from gaining access to areas under a tile roof, is another edge-of-roof issue. Those cozy, cave-like areas make great nesting spots. Fine screening can keep the birds out and it can also protect from wildfire embers. Imagine a hot ember flying under a tile at the edge of your roof. It can burn slowly, out of site, under the fire resistant tiles.  A small bird’s nest could ignite, or the ember could reach flammable materials beneath the tiles.

Gutters are included in edge-of-roof concerns. Keeping them free of debris can diminish the fuel a wildfire needs to spread.

As a homeowner, you can take all the right steps, choose a great Class A roof covering, deal with edge-of-roof issues, and still fall short of protecting your home.

Ask your local fire department for their specific guidelines for defensible space around your home. It can vary depending on your local geography, but one thing is clear, wild overgrown greenery can pose a threat.

If you have further questions about the best fire resistant roofing material for your particular roofing project, contact us today. One of our professional roofers will be happy to help you.