Fire Retardant Roof Covering Class C

Obviously since wildfires and the fire season has become increasingly worse it is important to note the roofing materials that are the lowest rated.

Fire retardant roof covering class c.

The slope of the test specimen is preselected and since steeper slopes are more of a challenge due to melting material feeding the fire the rating applies to the maximum slope passed. Fire retardant surface coatings and other building materials. In this case the fire retardant treated shake is a stand alone class b covering. It means how your roof performs in a fire on the exterior of your property where coverings are installed on a non combustible or combustible deck.

The fire rating of a roof covering is either class a class b class c or unrated. Class a is the most fire resistant and should be the. The tendency is to assume that class a roof systems have a class a flame spread and so on but there is no correlation. Assembly rated class a roof coverings are those that meet class a standards when combined with other elements.

Class c fire resistant roofing material. If wood shakes and shingles are impregnated with fire retardant chemicals they meet the requirements for a class b fire rating and can meet a class a rating if additional materials are included in the roof assemblies. Wood shake plywood or particle board roof are the most common roofing types listed as class c. The maximum flame spread is 6 feet for a class a rated roof 8 feet for class b and 13 feet for class c.

A standard fire test is used to determine the fire rating of a roof covering. For example shake roofing with a fire retardant treatment rates class b on its own but achieves a class a rating when combined with specified underlying materials such as type 72 roll roofing material. Fire resistant roofing materials have specific classifications. The rating is determined by a set of fire tests in a simulated fire.

The astm e 108 ul 790. This fire retardant treated wood shake roof covering is an assembly rated class a roof. The underlying gypsum glass fiber panel densdeck material provides additional protection and is required for the class a rating. Class b fire retardant treatment is effective against moderate fire exposures.

Tested roof systems are fire classified class a b or c where the most fire resistant roof assemblies are class a and class c is least resistant. Class c roofing materials. How fire resistant is your current roof. Class a b c roof coverings class a b or c roofing systems are sometimes confused with class a b c i ii iii flame spread categories above.