General building work permit checklist — King County, Washington
Assembled from King County’s own published permit rules. Every line below is quoted from a city document and linked to it. Nothing here is generated, estimated, or inferred from another jurisdiction.
Do you need a permit?
King County requires a permit for general building work.
King County enforces the Washington State Building Code (the state-adopted IBC/IRC with WAC amendments) plus King County Code Title 16, and publishes its own exempt-work list for unincorporated areas. Work generally not needing a permit: a storage shed 200 square feet or less accessory to a house or used for agriculture, fences 6 feet high or less, most retaining walls 4 feet high or less, roofing or siding replacement on detached one- and two-family houses, uncovered decks 30 inches or less above grade, interior finishes such as carpet, flooring, tile, paint and wallpaper, like-for-like window and door replacement, and roof-mounted residential solar PV weighing under 4 pounds per square foot. None of these exemptions apply if the property contains critical areas — wetlands, shorelines, flood zones, steep slopes, established clearing limits, historically sensitive areas, setback areas, or where total impervious lot coverage would be exceeded. On a great many rural King County parcels the critical-areas overlay pulls otherwise-exempt work back into the permit system. Separately, on-site septic and well work is permitted by Public Health - Seattle & King County, not the Permitting Division.
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Sources
- building — permit rules ↗verified August 2026
Other permits King County publishes rules for
Listed because the city publishes a separate rule for each type — not because this project necessarily triggers one. Whether it does depends on your scope of work.
- Deck permit checklist
- Fence permit checklist
- Shed permit checklist
- Water heater permit checklist
- Re-roof permit checklist
- Retaining wall permit checklist
- Electrical work permit checklist
BuildSpec is a reference, not the authority having jurisdiction. Confirm requirements with King County before you build.