Did You Know? | ROOFING ASSEMBLY FIRE EXPOSURE CLASSIFICATION
Underwriters laboratories.
Model building codes as well as city and county ordinances often refer to three UL roof assembly fire exposure classifications A, B and C. UL 790 (ASTM E108) Standard Test Methods for Fire Tests of Roof Coverings is the test that is performed to determine roof covering or roofing assembly fire exposure classification. Materials are intended to be installed in accordance with the UL listing and the manufacturers’ installation instructions.
FIRE EXPOSURE CLASSIFICATIONS:
CLASS A
Effective against SEVERE fire test exposures, afford a high degree of fire protection to the roof deck, do not slip from position and do not present flying brand hazard.
CLASS B
Effective against MODERATE fire test exposures, afford a moderate degree of fire protection to the roof deck, do not slip from position and do not present flying brand hazard.
CLASS C
Effective against LIGHT fire test exposures, afford a light degree of fire protection to the roof deck, do not slip from position and do not present a flying brand hazard.