Fire endurance of lightweight wood trusses in building construction

Abstract

Lightweight wood trusses are economical construction elements that combine high strength, light weight, and cost savings. The parallel-chord truss is one of the most common lightweight trusses used in commercial and residential occupancies today. Like all structural components, these trusses are arguably susceptible to failure when exposed to fire. This paper will address fire resistance concerns of parallel-chord, lightweight wood truss floor- and roof-ceiling assemblies, particularly their performance under fire conditions and their susceptibility to construction defects. Because evaluating the effect of fire exposure on both conventional and lightweight wood truss assemblies is so important, considerable supplemental background information on the standard fire test, as it applies to general types of construction, is also provided.