Fire Rating For Roof Materials

Stucco is often recommended as one of the best materials for boxing in hazardous eaves.

Fire rating for roof materials.

Our roof systems are rated by code for external fire resistance under deck exposure and time temperature resistance. The different roofing materials that are available for installation on your home are all evaluated for their fire resistant capabilities. The highest rating meaning the most fire resistant is classified as class a and is able to withstand severe fire exposure. Roof eaves overhangs are a fire hazard but they can be protected with an encasement of fire resistant material.

Here are the three rating categories you need to know. It is recommended in areas throughout the united states where forest fires are common. Pressure treated shakes and shingles are the most common roofing materials to fall under the class b rating. But by including a particular underlying material it can meet the requirements for a class a roof.

The brands consist of an ignited wood lattice placed directly on top of the test specimen. National or model building codes state canadian provincial building codes or fire codes require that roofs must carry at least a class c fire rating or better. We must emphasize however that individual roof components are not rated at all. Burning pieces of debris and if flames can spread across its surface.

This includes checking if the material is combustible whether it will splinter and generate flying firebrands i e. Roofing systems are rated by realistic fire tests. Class a roofing materials. Roofing fire ratings 101 roofing materials go through strenuous testing to determine a fire rating.

Stop fire and stay stylish. Both are burn through tests and the ultimate roof systems rating is the lowest of the three tests. Experience maximum flame spread of 13 feet. A one inch 2 54 centimeter layer of stucco can easily lend a 1 hour fire rating to a wall source.

Class c roofing provides only light fire protection. An exterior fire retardant treated shake roof has a stand alone class b rating. Withstand a burning brand measuring 1 5 x 1 5 and weighing 1 4 gram. The class a brand weighs 2 000 grams class b 500 grams and class c 9 1 4 grams.

Roofing with a class c rating is able to. Common underlying materials include a type 72 roll roofing material also known as 72 pound felt or 72 pound capsheet material and a panelized gypsum product called densdeck. The benefit of purchasing a class a roof is it can withstand severe exposure to fire and has the highest rating compared to class b and class c. Federal housing administration fha and other lenders require that building roofing materials conform to these standards.

The rating scale is relatively simple and is rated from a to c.