Deck Questions Homeowners in Seattle Ask

A 12 by 16 foot deck, a common size for Seattle backyards, runs near $10,500 at roughly $55 per square foot, according to a Kirkland builder. Composite, a raised deck or a sloped lot will move that number; the cost guide ranks why.

A new deck on the Eastside typically takes 2–4 weeks to build. Permitting sits in front of that: the city issues some simple permits with minimal review within 48 hours of application, while decks that need full plan review take longer. See the permit guide.

If the frame is sound, yes, and it costs less than a new deck: re-decking a sound frame runs $55–$75 per square foot against $70–$95 for a new composite deck. Have the ledger, joists and posts checked first; deck repair and replacement explains what to look at.

No, but it raises the upkeep. In this climate a cedar deck wants restaining every two to three years at $6–10 per sq ft, and local builders recommend cedar mainly for south-facing, well-drained flat lots. Compare wood and composite on your own lot's sun and drainage.

Only if it is designed for one. Seattle's minimum live load design for decks is 60 pounds per square foot. Whether a particular deck can carry a filled tub is a question for the builder or a structural engineer, not a rule of thumb. Bellevue lists a deck with spa under its addition permit. Tell the company about the tub in your first request.

Height, footings and paperwork. A West Seattle deck cantilevered over a hillside needs engineered beams, deeper footings and often a geotechnical letter, which can add $4,000 – $12,000. If the lot is in a landslide-prone environmentally critical area, the city requires a pre-application site visit before any construction permit.

An Eastside builder says a pressure-treated, cedar or composite deck recoups ~65–83% of its cost. Treat that as a contractor's figure, not an appraisal of your home.