FAQ

When it comes to wildfires, roofs and exterior siding are the most vulnerable due to their prolonged exposure to the elements, specifically embers during wildfires.

Stucco doesn’t actually burn, however it has what’s called a spalling effect which causes the trapped oxygen within the porosity of the stucco to explode, thus leaving what is behind it (usually wood) to burn.

Fire ratings rank a material’s surface burning characteristics according to how fast flames spread and how much smoke they produce, according to ASTM (American Society for Testing and Materials). The most common test for determining a fire rating is the Test Method E-84, or the tunnel test, which measures how far and fast flames spread across the surface of a given sample material. The results are then classified into three flame spread rating (FSR) groups, Class A-C. Cement would be considered Class A with 0-25 FSR, and untreated oak plywood ranks at class C with 125-185 FSR.

Is there an Extended Class A Flame Spread Rating?

Yes, the test for Extended Class A Ratings are designated as E-2768.  Wood siding treated with Sun FireDefense’s SPF3000 earned an Extended Class A Flame Spread Rating from Guardian Fire Testing Laboratories (see report here).

Intumescent, which passively helps increase a building’s resistance to fire, and SPF3000 work differently when reacting to heat. When heated, solutions mixed with intumescent expand and harden on top of whatever material it is coating. Once activated, it hardens and renders the material it’s covering, especially wood, unsalvageable and damaged. Alternatively, once activated by heat, SPF3000 expands into the material it is coating, extinguishing fires by preventing oxygen from feeding the flames. Once the heat is removed, SPF3000 contracts to its original state without damage to the surface it covers.

Intumescent coatings are also mostly used on commercial buildings. The solution is more expensive and requires more product per application as it needs a 15-20 ML thick coating to be effective vs. 3-5 ML with SPF3000. Sun FireDefense’s SPF3000 clear coat paint can also last through several extreme heat and fire events, whereas once intumescent coatings are activated, they need to be reapplied.

Coating a 5000 sqft home with SPF3000 would take approximately 3 – 5 days depending on the prep work required to mask windows and cover shrubs and plants. 

SPF3000 works best on wood, stucco, and fiberglass siding; plus, wood and composite roof shingles. These materials have porous qualities that allow the clear coat paint to expand into whatever it is coating to block oxygen to the substrates and extinguish flames.  SPF3000 is not required on cement siding or roof shingles.