Wildland Urban Interface (WUI) Code Updates
The International Wildland-Urban Interface Code (often referred to as “WUI”) is aimed at reducing wildfire risks to people and property. Changes to code have been approved at the state level that will impact construction in King County of buildings and structures where permit applications are deemed complete after the implementation date, currently set for March 15, 2024.
Implementation date note: The initial implementation date was July 1, 2023. However, the State Building Code Council (SBCC) has voted twice, on May 24, 2023, and September 15, 2023, to delay the implementation of the 2021 Washington State Building Codes. The current implementation date is now March 15, 2024.
Background and general requirements
The Washington State Legislature has adopted the 2021 International Code Council (ICC) codes. The Wildland-Urban Interface Code is part of this code. Beginning on March 15, 2024, projects not currently vested must meet these code requirements, which could have a significant impact on proposed construction.
The WUI code adds fire protection standards to all structures based on proximity to areas with "vegetative fuels" that can contribute to wildfires even if permits are not required. The WUI code specifies requirements for 1) driveway access to buildings and structures, 2) ignition-resistant construction requirements for buildings and structures, including decks, and 3) creation and maintenance of defensible space around buildings.
Where does this apply?
Determining if a property a project will have to comply with requirements of the WUI code can be done by consulting the WA Department of Natural Resources Map or by consulting the King County iMap and navigating to the Wildland Urban Interface layer under the Planning layer group.
Resources and links
- To read the 2021 IWUIC (as adopted and amended by WA State), visit: Washington Wildland-Urban Interface Code 2021 or Washington State Building Code Council
- For additional information on Community Wildfire Resilience and Preparedness, visit: Department of Natural Resources Wildfire Resilience and Preparedness
- For additional information on incorporating wildfire-resistant building materials and landscaping into your home, visit: Wildfire Risks Ignition-Resistant Homes
- For a high-level explanation of the WUI, view the WA Department of Natural Resources Wildland-Urban Interface StoryMap
- To view the WA Department of Natural Resources interactive map depicting WUI designated areas, visit: Washington State's Wildland Urban Interface (WUI) Map
- To view mapping for the Wildland Urban Interface areas within King County, visit the King County iMap Portal. Under the layers list select "planning" and expand to show all planning options, then select "Wildland urban interface area".
- King County Assistance Bulletin (coming soon, in development) - (PDF)