Fire Rating

roof 0 Comments March 8, 2017June 21, 2017 Uncategorized

Fire ratings as applied to roof coverings on combustible or non-combustible surfaces are laboratory ratings given to flame spread distances. For instance, having a Class A rated roof may refer to a flame spread of 5 feet, 8 feet flame spread for a Class B roof surface and for a Class C is for a 13 foot flame spread. Steeper slopes are more of a challenge to laboratory ratings.

Class A does not mean that the materials are Grade A. A thinner roof system may have a better fire retarding performance than a thicker surface since it contains less fuel to feed the fire.