Seattle Deck Permit Guide: What Every Homeowner Needs to Know

Seattle building code (and most King County cities) requires a permit for: Always requires permit: • Any deck attached to the house (requires a permit regardless of size or height) • Any freestanding deck over 200 sq ft • Any deck more than 30 inches above the adjacent grade Generally does NOT require permit: • A freestanding deck under 200 sq ft AND under 30" off grade • Deck repairs that don't change structure, size, or height • Re-decking (replacing boards only) on an existing legal deck When in doubt, call your city's permit office or ask us — we know the local requirements in every city we serve.

Here's what the deck permit process looks like in Seattle: Step 1: Design and drawings — We prepare construction drawings showing dimensions, framing, and materials. Step 2: Permit application — Submitted online through Seattle's permit portal (or in person for other cities). Step 3: Plan review — A city plans examiner reviews the drawings for code compliance. For simple residential decks, this is often "over-the-counter" (same day) or takes 1–3 weeks. Step 4: Permit issuance — Once approved, the permit is issued and construction can begin. Step 5: Inspections — Most decks require a framing inspection (before decking goes on) and a final inspection. We schedule these with you. Step 6: Approval — Final approval closes the permit and documents the project for your records. Vikings Exterior handles every step of this process. You don't need to call the city or navigate the portal — we do it all.

Unpermitted decks are a growing problem in Seattle's real estate market. Here's what homeowners need to know: If you're buying: Have the deck inspected by a structural engineer. An unpermitted deck may have code violations that will require expensive correction. Some lenders require permits to be in order before funding. If you're selling: An unpermitted deck will come up in the home inspection. Buyers will either request a price reduction or require you to legalize the deck before closing. Legalizing an existing deck can cost $2,000–$8,000 depending on what corrections are required. If you're planning to build: Always permit your deck. An unpermitted deck creates liability if someone is injured, complicates your homeowner's insurance, and creates headaches when you eventually sell. We only build permitted decks. If you're considering a contractor who skips permits "to save time," consider what that actually costs you.