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Class A Fire Rating

Crawl spaces should be insulated with materials that have a Class A fire rating.

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Homeowners rarely think about the sort of material that’s used to insulate their crawl space or basements. The ugly truth is that many types of insulators – especially foam boards – are combustible and aren’t suitable for the crawl space area. What your crawl space needs is Class-A-rated insulation that is also treated with pest repellent or insecticide.

Different construction materials burn up at different rates when they catch fire. Here, we’ll shed light on the Class A fire rating so you can understand how you can protect your home and assets.

What Is the Class A Fire Rating?

The Class A fire rating is the highest standard given to building or insulation materials in the construction industry. These materials have a flame-spread rate of between zero and twenty-five. Because of what they are treated with during manufacturing, Class-A-rated materials tend to spread flames slower than other materials. It’s this property that makes them effective against various fires, particularly those arising from combustibles.

Fire-Resistance Rating

The fire-resistance rating refers to how long a material can hold out against a fire. Engineers and fire experts use design documentation, comparative ratings of various materials, and established standards to determine fire resistance ratings.

The North Carolina State Building Code requires every residence to meet stringent fire safety regulations as stipulated by the local codes. For instance, Chapter Nine of the North Carolina Fire Code requires homes and buildings to have passive and active fire safety systems. You’re also not allowed to use flammable materials in hidden spaces.

The next time you decide to renovate your home or repair the crawl space, take time to determine the fire resistance ratings of various building materials used, especially insulation. If you’re not sure, consult an engineer or home inspector.

Building Materials

Whether you’re building a simple family home or a condo, you should use fire-resistant techniques and materials with Class A ratings, as they’re not combustible.

Roofing systems: Almost every roofing material has a unique fire rating. We recommend asphalt, concrete, clay tiles, and fiberglass shingles as these provide better fire protection.

Walls: Your walls also require fire protection. Rising from the foundation, fire-resistant walls can be a formidable defense against fire hazards. These types of walls can stop a potential fire from breaking out and contain its spread.

Crawl space and basement: Covering the walls of your basement and the crawl space with fireproof insulation such as foam board or spray foam also helps deter potential fires.

 Insulating Your Crawl Space

The best way to insulate your crawl space is to cover it with insulation board from the ground up. What this does is turn it into a conditioned space just like a basement.

We recommend ExTremeBloc™, a two-inch thick board that’s designed for below-grade areas. This material is infused with termiticides that will kill termites that try to tunnel through your foam board insulation. Best of all, it has a higher R-value per inch and is durable.

We can frame a 2 x 4 or 2 x 6 wall one inch away from your concrete wall. Raising the board will keep it from being in contact with the damp ground and moisture. For hard-to-reach areas and cavities, we will use spray foam that creates a moisture and air seal and fills small holes. We will leave sufficient space just in case you’d like to do the wiring.

Ways of Protecting Your Home

Accidental fires are a safety hazard in any home. That’s why local codes stipulate stringent preventative measures for homeowners in Colorado. These include installing fire protection systems and keeping them in top shape.

Another thing you can do to enhance fire safety is to cover your crawl space and basement walls with fireproof materials. Besides stopping a fire from spreading, these materials also regulate thermal differences between your home’s interior and the crawl space. Your rooms will remain warm in the freezing winter, and cool in the hot summer.

You can leverage open space and erect fireproof walls as passive fire protection steps. These will slow down the spread of fire around your home. For ultimate protection, we recommend materials that combine waterproofing, fire protection, and heat retention properties.

Would you like to seal your vents and apply foam board insulation to your crawl space walls? Contact Tarheel Basement Systems for a free insulation inspection and quote. We can help you create a dry, comfortable crawl space that’s also pest-free and usable. 

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717 Green Valley Rd, Suite 200
Greensboro, NC 27408

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3333 Air Park Road
Fuquay-Varina, NC 27526

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2910 Griffith Rd
Winston-Salem, NC 27103