Coffee Break Training: Building Construction: Heavy Timber Construction (Type IV)   [open pdf - 498KB]

"Building codes classify different methods of construction into five 'types' for the purposes of establishing requirements for size, height, fire resistance, life safety, occupancy and fire protection. (See Coffee Break Training FP-2009-45 for a summary.) One of these categories is known as heavy timber construction (Type IV) due to its reliance on heavy solid or laminated wooden components in the structural framing. Typically, heavy timber construction buildings have noncombustible (usually masonry) exterior walls, but the model building codes allow fire-retardant-treated wood framing in exterior wall assemblies with a two-hour fire-resistance rating or less. Where a horizontal separation of 20 feet (6096 millimeters) or more is provided, wood columns and arches conforming to heavy timber sizes are permitted to be used on the weather side of exterior walls. Concealed spaces (such as drop ceilings, roof/ceiling assemblies, floor/ceiling assemblies or other enclosed spaces where fire could hide) are not permitted."

Report Number:
Coffee Break Training - Fire Protection Series No. FP-2013-22
Public Domain
Retrieved From:
United States Fire Administration: http://www.usfa.fema.gov/
Media Type:
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