NFPA classifies building construction into five classes based on

• A. How the building is used
• B. Emergency Access
• C. The fire resistive materials used
• D. Occupant load factors and area of the building

Answer: (C)

NFPA classifies building construction by how fire-resistant the structural elements and enclosing materials are. This means the five construction types are defined based on the fire-resistance ratings and the materials used to build the frame, walls, floors, and roof. For example, Type I is fire-resistive, Type II is noncombustible, Type III has noncombustible exterior walls with a different interior framing, Type IV uses heavy timber, and Type V is typically wood frame. This framework matters because it influences how a building will respond in a fire, including how long it can maintain structural integrity and contain fire spread. Factors like how a building is used, emergency access, or occupant load and area affect design for safety and egress, but they do not determine the five construction types.