Do I Need a Permit for My Deck?
In most Eastside cities and Seattle, a deck needs a building permit if any part of it is more than 30 inches above the ground, if it carries a roof, or if it supports a hot tub; some cities also require one for any deck attached to the house. Ground-level decks, small open pergolas and paver patios often do not. This checker tells you which applies to your project in your city, what to submit and roughly how long review takes.
Your permit picture
We prepare and submit the permit with every project that needs one.
Get a Free Design & QuoteThe rules that apply almost everywhere
- Decks more than 30 inches above grade at any point need a permit and a guard.
- Any roofed structure, attached or freestanding, needs a permit.
- Hot tubs on decks need a permit for the structure and the electrical.
- Gas lines, plumbing and electrical circuits for kitchens and fire features need trade permits.
- Work in critical areas, shorelines or tree protection zones needs review even when the structure itself would otherwise be exempt.
What changes city to city
| Topic | How cities differ |
|---|---|
| Low attached decks | Some cities exempt them; others require a permit for any deck attached to the house |
| Pergolas | Exempt below a size and height in some cities; permit required for attached or large ones |
| Lot coverage | Roofed structures count in most cities; open pergolas and decks often do not |
| Setbacks | Accessory structures have city-specific side and rear setbacks |
| Trees | Kirkland, Mercer Island and Seattle review tree impacts closely |
| Review time | From a few weeks for simple decks to months for hillside or shoreline projects |
Why a permit is worth it
A permitted deck has been checked for footing size, ledger attachment and guard strength, the three things that cause deck collapses. The permit record also matters at sale: buyers' inspectors and lenders ask about unpermitted elevated decks, and the answer can cost more than the permit would have. What goes into the submittal and how review runs is in Deck Permits on the Eastside Explained.
Sources
Rules are drawn from each city's building and land-use codes and permit-center guidance, and from the residential code Washington adopts statewide.
Deck permit questions
My old deck never had a permit. Does my replacement need one?
Yes, if the new deck meets any of the permit triggers.
Do I need a permit to replace deck boards?
Usually not, if the framing is not changing.
Can I pull the permit myself?
Yes. We provide drawings either way, and we submit for clients who prefer us to.
What if my HOA approves it?
HOA approval is separate. A project can need both, and neither replaces the other.
Need the drawings? We prepare them with every quote that needs a permit.