Status of Building Code Allowances for Tall Mass Timber in the IBC
Jurisdictions that have adopted the tall mass timber code provisions in the 2021 International Building Code (IBC), either in whole or with local amendments.
Status as of April 2022
The 2021 International Building Code (IBC) has been published and is available for purchase through the International Code Council. This version of the code includes three new construction types—IV-A, IV-B and IV-C—that allow the use of mass timber or noncombustible materials in buildings up to 18, 12 and nine stories (respectively).
The following jurisdictions have adopted the tall mass timber provisions in the 2021 IBC, either whole or with local amendments.
- Oregon – Appendix P Tall Wood Buildings within the 2019 Oregon Structural Specialty Code
- Washington – Washington State Building Code
- City of Denver, Colorado – Appendix U Tall Wood Buildings (page 187) within the 2019 Denver Building Code
- Utah – Chapter 2a: Tall Wood Buildings of Mass Timber Construction, incorporated as part of the State Construction Code
- California – Supplement to the 2019 California Building Code
- Virginia – Supplement 2021 IBC Mass Timber Provisions within the 2018 state building code
- City of Austin, Texas – Ordinance No 20210603-059, adoption of the 2021 IBC (effective September 1, 2021)
- Maine – Emergency Rule 3, amendments to the Maine Uniform Building and Energy Code (Section 5, item 25)
- City of Bryan, TX adoption of the 2021 IBC
- Georgia – Appendix P to the 2018 IBC
- Idaho – Amendments to the Idaho Building Code
- Howard County, Maryland – adoption of the 2021 IBC
- Texas Jurisdictions:
Other jurisdictions are considering adoption of the tall mass timber provisions including:
- Wisconsin – The state’s Commercial Building Codes Council has been instructed by Department of Safety and Professional Services Secretary-designee, Dawn Crim, to closely evaluate the possibility of tall mass timber code adoption.
For more information on the code changes, including design implications of the new construction types, see this WoodWorks paper and the ICC/American Wood Council document, Mass Timber Buildings and the IBC.
Proposed changes to the 2021 IBC, which would be reflected in the 2024 IBC if approved, are currently undergoing the ICC code and committee review process. Several changes have been proposed that would affect aspects of tall mass timber design and construction. Further information will be available as these changes are put to vote in late 2021.
For free project assistance related to the design of tall mass timber projects, or for general education related to the tall mass timber-related code changes, contact the WoodWorks Regional Director local to you. For information on the safety of tall mass timber buildings, development of the code changes and other related topics, see resources available from the American Wood Council and the Mass Timber Code Coalition.