Which statement about Class 'A' roofing rating is true?

• A. It is the second-highest rating and applies to all roof types.
• B. It is the highest fire-resistance rating and indicates resistance to severe exposure from external fire sources.
• C. It is a rating unrelated to exterior fires.
• D. It is no longer used in modern roofing.

Answer: (B)

Class A is the strongest fire-resistance rating for a roof assembly, meaning it can resist severe exposure to an exterior fire source. This top rating comes from standardized tests that simulate flames and radiant heat hitting the roof from outside a building, and it applies to the particular roof assembly (the combination of covering, underlayment, deck, etc.). Because it’s the highest category among the standard classifications, a Class A roof offers the greatest resistance to flame spread and heat transfer compared with Class B or Class C. It’s still used today and is often required or favored by codes and insurers. The other statements don’t fit because the rating is not the second-highest, it does relate to exterior fires, and it remains in use in modern roofing.