AWC Applauds Denver’s Adoption of Tall Mass Timber Codes

Jan 06, 2020

LEESBURG, VA. – The City of Denver voted on December 23, 2019, to adopt the 2019 Denver Building Code, which includes the tall mass timber code provisions approved for the 2021 International Building Code (IBC).

As part of the adoption of the new code, there will be a four-month period where new projects can use either the 2016 Denver Building Code or the newly-adopted 2019 version. After four months, all building and fire code permits will be processed under the 2019 Denver Building Code.

“We congratulate the City of Denver on incorporating mass timber into its building codes, and recognizing the potential of this new category of wood products to revolutionize the way America builds,” said American Wood Council President & CEO Robert Glowinski. “Mass timber offers the strength of historic building materials with lower weight, and, in the rare event of a fire, has inherent fire resistance. Beyond the aesthetic qualities of mass timber that building owners and designers are seeking, wood is among the most energy-efficient and environmentally friendly of all construction materials, storing carbon from the atmosphere for long periods of time.”

The adopted proposal to recognize mass timber in the new code was submitted by Dr. Gregory R. Kingsley on behalf of the Structural Engineers Association of Colorado. The American Wood Council provided technical assistance to the City in support of the proposal. The 2019 Denver Building Code will now recognize three new types of construction that also are included in the 2021 IBC:

  • Type IV-A – Maximum 18 stories, with gypsum wallboard on all mass timber elements.
  • Type IV-B – Maximum 12 stories, limited-area of exposed mass timber walls and ceilings allowed.
  • Type IV-C – Maximum 9 stories, all mass timber designed for a 2-hour fire resistance.

Fire tests conducted at the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives National Fire Research Laboratory demonstrated that the fire performance requirements for these new tall mass timber construction types are conservative, and in most cases more conservative than the performance required in the current building code.

Find more information about tall mass timber buildings here: awc.org/tallmasstimber.

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