4 county-level rules, plus city-specific rules for 1 city in King County, Washington.
Verified from official government sources
In unincorporated King County, storage sheds of 200 square feet or less do not require a building permit when accessory to a residential home and used for agricultural or storage purposes. Sheds over 200 square feet require a building permit. All sheds must comply with zoning setbacks.
Fences under 7 feet in height generally do not require a building permit in unincorporated King County. Fences must comply with KCC Title 21A zoning height limits (typically 6 feet rear/side, 4 feet front). Retaining walls over 4 feet require permits. Fences in critical areas may need additional review.
Decks not exceeding 200 square feet and not more than 30 inches above grade are generally exempt from permits in unincorporated King County. Larger or elevated decks require building permits. Concrete patios at grade do not require permits. Decks in flood zones or critical areas have additional requirements.
Most renovation work in unincorporated King County requires a building permit. Cosmetic work (painting, flooring, cabinets) is exempt. Structural, electrical, plumbing, and mechanical work all require permits. King County adopts the Washington State Building Code, based on the International Residential Code.
1 cities in King County have their own permit requirements rules. Each link goes to that city's dedicated page with code citations.
See every category we cover for King County — parking, noise, fences, fires, animals, pools, and more.
King County Ordinance Hub →