Tall Mass Timber Toolkit
Understanding the Tall Mass Timber Code Changes: A Toolkit for Fire Officials follows the International Code Council's approval of code changes allowing for the construction of tall mass timber buildings up to 18 stories for the 2021 edition of the International Building Code. This document provides a recommended sequence for review that should give a comprehensive understanding in an efficient and most-easily understood manner. The toolkit provides detailed comparisons of new types of timber construction and differences from traditional dimension lumber, and offers an overview of the primary fire protection features which will now be required for mass timber buildings.

2021 IBC Approved Code Change Resources
Building Officials Guide to Tall Mass Timber Code Changes
17 Tall Mass Timber Code Changes Recommended for Approval
- IBC Section 602.4 Type IV construction (G108-18)
- IBC Section 703.8 (new) Tested noncombustible protection contribution (FS5-18)
- IBC Section 722.7 (new) Calculated noncombustible protection contribution (FS81-18)
- IBC Section 703.9 (new) Sealing of adjacent mass timber elements (FS6-18)
- IBC Section 718.2.1 Fireblocking materials (FS73-18)
- IBC Section 403.3.2 and IFC Section 914.3.1.2 High rise sprinkler water supply (G28-18)
- IFC Section 701.6 Owner’s responsibility (F88-18)
- IFC Section 3308.4 (new) Fire safety during construction (F266-18)
- IBC Table 504.3 (G75-18) Allowable height in feet
- IBC Table 504.4 (G80-18) Allowable number of stories
- IBC Table 506.2 (G84-18) Allowable area
- IBC Section 3102.3 Special construction (G146-18)
- IBC Appendix D Section D102.2.5 Fire Districts (G152-18)
- IBC Sections 508.4.4.1 and 509.4.1.1 (new) Fire barriers at separated occupancies and incidental uses (G89-18)
- IBC Section 2304.10.1 (new) Fire resistance of connections (S170-19)
- IBC Section 1705.5.3 (new) and Table 1705.5.3 (new) Special inspection provisions (S100-19)
- IBC Section 110.3.5 (new) Inspection of protection for connections (ADM35-19)
2021 IBC, 2018 Group A, Tall Mass Timber Proposals Review Guide
What the Fire Service Needs to Know about Tall Wood Buildings, Firehouse.com
Accommodating Mass Timber Buildings — the Right Way to Change the Building Code, Firehouse.com
Examples of Tall Mass Timber Buildings
Tall Mass Timber Buildings are growing in popularity because of their strength, resilience and efficiency.
Tall Mass Timber – Fire Safe and Code Compliant
In 2016, the International Code Council (ICC) appointed a balanced committee of building officials, fire officials, architects, fire protection engineers, and industry experts to examine and if appropriate propose building code changes to allow for tall mass timber buildings. The changes create three new construction types in the 2021 International Building Code allowing tall mass timber buildings to reach a maximum of 18 stories.
However, despite years of objective, rigorous testing which informed these code decisions, some still question the safety of tall mass timber – particularly fire safety.
In his recent article in Fire Engineering, Raymond O’Brocki, Manager of Fire Service Relations for the American Wood Council (AWC), reviews these code changes to dispel safety concerns, and ensure confidence in mass timber as well as the ICC’s independent and reliable code development process.
In response to fire safety concerns regarding increased height for wood buildings, including dependence on fixed fire protection systems and the need for additional training and pre-incident plans, O’Brocki notes that:
- The fire resistance rating for the tall mass timber structure is three hours in buildings above 12 stories and two hours in all others.
- The only specialized firefighter training needed to respond to a tall mass timber building is training in high-rise operations. These buildings will perform as any high-rise building in the event of a fire.
- The tall mass timber code changes include a section on owner’s responsibility which requires a third-party inspection of all passive fire protection annually. This would not require any special knowledge of a fire inspector to review the third-party inspection report and is identical to reviewing annual fire alarm and sprinkler reports during the annual inspection.
Our nation’s building codes have never been stronger than they are today. As construction innovations evolve, the safety of firefighters and first responders remains AWC’s top priority. We are confident that ICC will also continue to strengthen research and testing when determining code changes – and tall mass timber is no exception.
To learn more about the recent tall mass timber code changes and fire safety requirements, read Raymond O’Brocki’s Fire Engineering article, “Tall Mass Timber Buildings and Fire Service Concerns.”