Which type of roofing material cannot be used by a roofing contractor?

Which type of roofing material cannot be used by a roofing contractor?

• A. Class A
• B. Class B
• C. Class C
• D. Class D

Answer: (D)

Roofing fire classifications determine what materials are permitted for a roof covering. In practice, roof coverings are tested and assigned a fire-resistance rating of Class A, Class B, or Class C, with Class A offering the highest fire resistance. There is no recognized Class D rating for roof coverings in the standard codes. Because the code requires a rating of A, B, or C, a material that would be designated as Class D would not have an approved fire rating and cannot be used as a roof covering. So the type that cannot be used is the one with a Class D designation, since it isn’t an allowable fire-rating for roofing materials.

Roofing fire classifications determine what materials are permitted for a roof covering. In practice, roof coverings are tested and assigned a fire-resistance rating of Class A, Class B, or Class C, with Class A offering the highest fire resistance. There is no recognized Class D rating for roof coverings in the standard codes. Because the code requires a rating of A, B, or C, a material that would be designated as Class D would not have an approved fire rating and cannot be used as a roof covering. So the type that cannot be used is the one with a Class D designation, since it isn’t an allowable fire-rating for roofing materials.