Which construction type is defined by the use of heavy timber as the principal structural material?

Which construction type is defined by the use of heavy timber as the principal structural material?

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

Answer: (C)

Heavy timber framing is the defining feature of this construction type. In this approach, the main load-bearing structure is built from large timber members—columns, beams, and floor/roof assemblies—whose substantial size gives them inherent fire resistance because the wood chars slowly and maintains structural capacity for longer under fire exposure. Because the primary material is wood rather than steel or concrete, this type is categorized separately from the noncombustible types and from mixed types where wood is used only for non-structural components or exterior walls. Exposed heavy timbers are common, and the system relies on the timber’s mass and charring behavior to meet fire resistance requirements while supporting structural needs. So, the best answer is Type IV, the heavy timber construction.

Heavy timber framing is the defining feature of this construction type. In this approach, the main load-bearing structure is built from large timber members—columns, beams, and floor/roof assemblies—whose substantial size gives them inherent fire resistance because the wood chars slowly and maintains structural capacity for longer under fire exposure. Because the primary material is wood rather than steel or concrete, this type is categorized separately from the noncombustible types and from mixed types where wood is used only for non-structural components or exterior walls. Exposed heavy timbers are common, and the system relies on the timber’s mass and charring behavior to meet fire resistance requirements while supporting structural needs. So, the best answer is Type IV, the heavy timber construction.