What classification is given to roof assemblies effective against severe fire-test exposure?

The classification given to roof assemblies that are effective against severe fire-test exposure is Class A. Roof assemblies are tested to determine their fire resistance, and Class A is the highest rating, indicating that the materials used can withstand severe fire exposure without igniting or allowing flames to spread. This classification means that such roofs have demonstrated the ability to resist fire for a prolonged period, which is critical in urban areas or regions prone to wildfires, where maintaining the integrity of a roof from fire hazards is vital for safety and building longevity.

Class B and Class C roofs offer moderate and light fire resistance, respectively, but do not meet the stringent standards set for Class A. Class D is not a recognized classification for roof assemblies in terms of fire resistance. Understanding these ratings is essential for inspectors and builders to ensure compliance with building codes and provide protection against fire hazards.