King County, WA Building Safety: Building Permits (2026)
Key Facts
- Governing code
- King County Code § 16.02.255
- Applies to
- Unincorporated King County only
- Finish work exempt
- Painting, flooring, cabinets (§16.02.240)
- Site plan waived if
- No use/bedroom/footage change
- Enforcing agency
- Dept. of Local Services, Permitting Division
Summary
Unincorporated King County requires a building permit for most interior renovation work; simple finish work like painting, flooring, and cabinets is exempt, and a site plan is waived for alterations that don't change use, add bedrooms, or increase square footage.
A site plan shall not be required for building permits when the scope of work proposed in the permit application is limited to interior alterations and does not result in the following: A. A change in use; B. Additional sleeping quarters or bedrooms; C. Nonconformity with Federal Emergency Management Agency substantial improvement thresholds; or D. An increase in the total square footage or valuation of the structure thereby requiring upgraded fire access or fire suppression systems;
Full Breakdown
King County Code § 16.02.255 waives the site-plan requirement for building permits limited to interior alterations, so long as the work doesn't change use, add sleeping quarters, trigger FEMA substantial-improvement thresholds, or increase square footage/valuation enough to require upgraded fire access or suppression. Section 16.02.240 separately exempts only cosmetic finish work, painting, papering, tiling, carpeting, cabinets, and countertops, from needing a permit at all. Everything else inside the walls (structural, electrical, plumbing, mechanical changes) still needs a full building permit from the Department of Local Services, Permitting Division, before work starts. This applies only in unincorporated King County, Seattle, Bellevue, Kent, Renton, and other cities issue their own permits.
Violations & Fines
Doing interior work that needs a permit without one is a code violation; King County Code Title 23 governs notices, stop-work orders, and enforcement, and unpermitted work can complicate a home sale or refinance.
Frequently Asked Questions
Do I need a permit to remodel a bathroom or kitchen in unincorporated King County?
Does Seattle use King County's renovation permit rules?
Is a site plan required for an interior remodel?
Sources & Official References
Other rules in King County
Compare King County to another location·View the Washington building safety overview
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