Which construction type is associated with curved or vaulted ceilings that use glue-laminated beams which may fail in a fire?

• A. Type I
• B. Type II
• C. Type III
• D. Type IV

Answer: (D)

The situation points to heavy timber construction, where large wood members and engineered wood products are used for the structural frame, often enabling curved or vaulted ceilings. Glue-laminated beams are a classic example of that type of construction. In a fire, these wood elements can lose strength as the adhesives degrade and the timber chars, potentially leading to failure or collapse if exposed long enough or not adequately protected. That’s why the description fits Type IV, which is defined by heavy timber framing rather than noncombustible or fire-resistive systems. Other construction types rely on metal, concrete, or masonry with limited exposed wood, so they wouldn’t typically be described as having curved ceilings built with glue-laminated beams that may fail in a fire.