Fire Rating For Roof Materials

If the roof deck is combustible such as wood plywood or osb two additional tests must be conducted.

Fire rating for roof materials. Pressure treated shakes and shingles are the most common roofing materials to fall under the class b rating. The highest rating meaning the most fire resistant is classified as class a and is able to withstand severe fire exposure. Our roof systems are rated by code for external fire resistance under deck exposure and time temperature resistance. We must emphasize however that individual roof components are not rated at all.

Roofing systems are rated by realistic fire tests. Withstand a burning brand measuring 1 5 x 1 5 and weighing 1 4 gram. An exterior fire retardant treated shake roof has a stand alone class b rating. Stucco is often recommended as one of the best materials for boxing in hazardous eaves.

Both are burn through tests and the ultimate roof systems rating is the lowest of the three tests. Roofing with a class c rating is able to. Federal housing administration fha and other lenders require that building roofing materials conform to these standards. 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.

Burning pieces of debris and if flames can spread across its surface. Stop fire and stay stylish. 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.

This includes checking if the material is combustible whether it will splinter and generate flying firebrands i e. 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. Class a roofing materials. The brands consist of an ignited wood lattice placed directly on top of the test specimen.

The rating scale is relatively simple and is rated from a to c. Class c roofing provides only light fire protection. The different roofing materials that are available for installation on your home are all evaluated for their fire resistant capabilities. Roofing fire ratings 101 roofing materials go through strenuous testing to determine a fire rating.

Some roofing materials such as untreated wood are unrated as they cannot meet even the minimum ratings for fire safety. It is recommended in areas throughout the united states where forest fires are common. Experience maximum flame spread of 13 feet. This rating indicates that the roofing materials limited to withstanding only light exposure to fire if the fire source is outside the building.

A one inch 2 54 centimeter layer of stucco can easily lend a 1 hour fire rating to a wall source.