King County, WA Fire Regulations: Brush Clearance (2026)

Unincorporated King County does not have a generalized brush-clearance ordinance requiring all parcels to be cleared each year. Vegetation management is instead addressed through the International Wildland Urban Interface Code for new construction in mapped hazard zones, through Firewise USA voluntary programs, and through nuisance abatement when overgrown vegetation creates a specific fire or public-safety hazard. In designated WUI areas, defensible space is required at permit issuance: a noncombustible Zone 1 from 0 to 5 feet around structures, a lean-clean-green Zone 2 from 5 to 30 feet, and a thinned Zone 3 from 30 to 100 feet. The King County Fire Marshal (206-296-6533) can order hazardous vegetation abatement on parcels that present an imminent fire threat. Removal of trees over 6 inches in diameter at breast height in critical areas requires a clearing and grading permit under KCC Title 16 and 21A.24, so brush clearance in streamside or forested parcels should be coordinated with the county. During red-flag warnings, outdoor burning is banned countywide; contact the Puget Sound Clean Air Agency for current burn status. Rural residents are encouraged to participate in Firewise USA community recognition programs.