Deck Permits Across the Seattle Area, City by City

Seattle is the strictest at 18 inches. The suburbs use 30 inches, but they measure and qualify it differently:

• Seattle, 18 inches. A permit is needed for a deck more than 18 inches above the ground, for a roof deck, and for any deck in an environmentally critical area. The platform exemption only holds when the structure is less than 18 inches above grade and not over a basement or other building story.
• Bellevue, 30 inches. No permit for installing or repairing a deck less than 30 inches above the ground. Above that, a permit with plan review, measured at the highest walking surface. The city's single-family addition permit covers adding less than 3,000 square feet or a deck to an existing single family residence.
• Redmond, 30 inches, detached only. Sidewalks, driveways and detached decks on private property are exempt when they are not more than 30 inches above adjacent grade and not over any basement or story below. Attach the same deck to the house and the exemption is gone.
• Renton, 30 inches plus a 5 foot ring. A building permit is required if the deck is more than 30 inches above grade including a 5 foot perimeter around the deck. On a sloping yard the ground inside that ring can fall away, which is how a low deck turns out to need a permit.
• Lynnwood, four conditions at once. The exemption covers decks not exceeding 200 square feet, not more than 30 inches above grade, not attached to a dwelling and not serving the exit door. Miss any one and the permit applies.
• Edmonds, 30 inches and uncovered. Uncovered decks are exempt only when they are no more than 30 inches above grade, not over any basement or story below, and not within a critical area.

Bothell is the one city here that does not publish a deck-specific height on its permit pages, so ask the counter rather than assuming. The Seattle permit guide goes further into the city's own rules, including setbacks and lot coverage.

Bellevue, Edmonds and Renton all name repair work in the trigger itself. Seattle does not.

• Edmonds requires a permit for the construction, repair, replacement, relocation, enlargement or alteration of decks.
• Bellevue requires a permit with plan review for installing, repairing, replacing and adding to decks more than 30 inches up, and separately for repairs to existing deck or porch handrails and stairs. Its addition permit lists the repair or replacement of existing deck structural framing as covered work.
• Renton includes repair and replace in its general permit trigger: construct, enlarge, alter, repair, move, demolish, convert, replace or install a building structure.
• Seattle lists decks by height, location and size instead, so a raised deck is in scope whether the work is new or remedial.

If rot in the frame is what prompted the question, deck rot and structural repair has the per-member costs and what a pro should probe before quoting.

Four of the seven price from the value of the work, one prices from the deck's size, and Seattle prices from how much review the job takes:

• Seattle. The fee follows the size and complexity of the project and the review it needs. A deck that qualifies for the subject-to-field-inspection permit pays only 40 percent of the plan review fee.
• Redmond. Each permit is based on the value of construction and can vary depending on which process applies. The city asks you to give an accurate value of construction when you request an estimate.
• Bothell. The project value is the cost submitted by the applicant or the city's own valuation calculation, whichever is higher, so a low figure on the form saves nothing. A 5 percent technology surcharge is added on top of most fees.
• Lynnwood. Fees are based on the size and complexity of the project, the value of the work, any additional permits, the time needed for review, and the inspection fees.
• Bellevue. Fees come in two parts: submittal fees paid at application, covering plan review and administration, and issuance fees paid when the permit and approved plans are issued, covering inspection. A Value of Improvements Form is one of the required documents.
• Edmonds. The odd one out, and the easiest to work out in advance: the fee is based on the square footage of the deck and stairs.

Renton is missing from that list on purpose. Its permit pages point to the city's own fee schedule rather than describing how a deck fee is set, so there is no method to quote. Wherever you are, the contract value you sign is the number the fee is built on, which is one more reason to have the quote itemised. The deck cost guide carries one local builder's permit budget for a Seattle deck.

Every one of the seven wants something beyond the deck drawing, and it is usually the item that stretches the timeline.

Seattle

In or near an environmentally critical area you need a pre-application site visit before applying for any construction permit. Placement is restricted once the deck is more than 18 inches up, and a deck more than 36 inches above the ground counts toward lot coverage.

Bellevue

Structural and lateral calculations and a structural plan are on the required-documents list, alongside a residential site plan and a stormwater site plan. For projects with less than 7,000 square feet of clearing and less than 100 yards of grading, the short-form construction stormwater pollution prevention plan may be submitted, and a backyard deck sits comfortably inside both limits.

Redmond

The city's residential permit page sends homeowners to the Washington L&I website to verify a contractor and to read the rules on acting as your own contractor. Worth doing before you sign anything; Redmond has the rest of the local detail.

Bothell

Trees. The city generally does not require a tree permit when, among other conditions, the lot is less than 20,000 square feet and there are no critical areas such as wetlands, streams or steep slopes greater than a 40 percent grade. A deck footprint often reaches into a tree's space, so settle it with a planner while the layout can still move.

Renton

Site work can add a second permit. A civil construction permit is required for site work involving more than 50 cubic yards of grading, more than 500 square feet of area cleared or disturbed, or more than 500 square feet of new or replaced hard surface. Pair the deck with a large new patio and you are in that territory.

Lynnwood

Difficult ground brings in an engineer. A geotechnical report is required where construction will occur in soft compressible soils, where there are landslide or seismic hazards, or where the foundation design calls for unique or deep foundations, and those reports must be stamped and signed by Washington State licensed engineers.

Edmonds

A Critical Areas Determination, issued by the Planning Division, must be completed and on file with the city before the deck permit is reviewed. Build that into the schedule rather than meeting it at submittal.

The contractor you hire, in almost every case. In most instances, if you have hired a contractor, the contractor is required to take out the permits, and Washington's own hiring guidance treats a builder who asks you to pull it as a warning sign. The practical reason is liability: whoever holds the permit answers for the inspection.

So the permit belongs on the written bid as a named line, with the fee either included or excluded in plain words. The deck builder hiring checklist lists what else the bid should spell out, and how we vet our deck pros covers the registration lookup we run first.

Measure the height the way your city measures it. Three of these cities define the measurement rather than just the number, and the definition is where low decks lose their exemption:

• Bellevue measures to the highest walking surface
• Renton counts grade across a 5 foot perimeter around the deck
• Lynnwood needs the deck no more than 30 inches above grade at any point, which on a sloped yard means the lowest corner of the ground rather than the average

Then check the three conditions that sink an exemption regardless of height: whether the deck is attached to the house, whether anything habitable sits below it, and whether the lot touches a critical area. A deck over a room is a different project, covered in leaking decks and waterproofing. If an old deck is coming out first, repair or replace prices both routes. Local detail sits on the pages for Bellevue, Redmond, Bothell, Renton, Lynnwood and Edmonds.