Building and fire codes

What code to use?

For applications deemed complete on or after March 15, 2024, the 2021 Washington State Building Code applies, including WA state amendments (found in Title 51 WAC) and King County Code (KCC) amendments (found in KCC Titles 16 & 17).

For applications deemed complete on or after February 1, 2021 and before March 15, 2024, 2018 State Building Codes are applicable, including WA state amendments (found in Title 51 WAC) and King County Code (KCC) amendments (found in KCC Titles 16 & 17).

Building code resources

International Building Codes

International Code Council (ICC)

Washington State International Codes

Washington State Building Codes

Washington State Building Code Council

Washington Association of Building Officials (WABO)

Residential Basics Program

The upcoming code change means the Registered Plans reviewed and approved under the 2018 State Building Codes will expire March 14th, 2024. The County has begun accepting applications for new Registered Plans based on the 2021 code as of January 16th, 2024. During the transition period (from January to March 2024), Basic permits may be issued for projects based on either the 2018 or 2021 registered plans.

Sprinkler system

If property owners are preparing to submit building plans for a residential building permit, you need to determine if there is a need to install an automatic fire sprinkler system. A separate permit is required before installing a sprinkler system.

Application information

Fire permits, sprinkler systems for residential and commercial

Wildland Urban Interface (WUI) Code – update postponed

The 2021 Wildlife Urban Interface Code is not in effect in King County.

The International Wildland-Urban Interface Code is aimed at reducing wildfire risks to people and property. The State Building Code Council had adopted parts of the 2021 edition of the code into WAC 51-55, to take effect along with other 2021 I-Codes on March 15, 2024.

But Engrossed Senate Bill 6120, passed and signed by the Governor during the 2024 Washington State Legislative Session, prevents the State Building Code Council from adopting a Wildland Urban Interface Code until the Department of Natural Resources completes new mapping.

So on March 15, the Washington State Building Code Council filed an emergency rule removing all language related to Wildland Urban Interface code adoption and amendment from WAC 51-55 until new mapping and amendments can be developed. This emergency rule is now in effect. It allows local jurisdictions to adopt the code on their own if they choose to do so. King County has not done this. The state and county will reassess adoption of the code when mapping from the Department of Natural Resources becomes available (expected in one to two years).

Learn more:

• Emergency Rule Adopted: Rescinding 2021 Wildland-Urban Interface Code – Washington State Building Code Council
• ESB 6120 (2023-2024) – Washington State Legislature Bill Information