Deck Builder in Kent, WA

A Deck in Kent Spends Half the Year Wet

Deck Builder Kent is a free referral service: send the form and one licensed local deck builder calls to quote. Installed decks here run about $35 to $75 per square foot, cedar low and composite high, and anything over 30 inches above grade needs a building permit.

Kent takes about 40 inches of precipitation a year, and the official gauge at Sea-Tac, seven miles up the road, records measurable rain on 156 days of it. The shape of that rain matters more to a deck than the total: October through January brings close to 22 inches, more than half the year, in the months when nothing dries between storms. A board that gets wet in July is dry by evening; one that gets wet in November stays wet until March. The Kent deck that lasts is the one built to shed water and dry out.

Where the water collects is predictable: behind the ledger board where the flashing is missing, on the top edge of every joist, at the base of a post that lands on soil instead of a footing, and in the end grain of stair stringers. A builder who works this climate every week knows those places and designs each one out. The form on this page reaches one who does.

The site covers a new deck, a replacement, a switch to composite on a sound frame, a repair, or a roof over the deck so it gets used between October and May.

What Makes Kent Decks Different From the Catalog Version

Split-levels and two-stories put the deck in the air

The bulk of Kent's single-family stock went up between the late 1970s and the 2000s, much of it on East Hill and around Panther Lake, and a large share of it is split-level or two-story with the main floor a full storey above the back yard. The deck off that kitchen door is six to ten feet up: tall posts, a bigger beam, stairs with a landing, a guard that takes a 200-pound push, and a ledger that carries the whole load, so the hardware and flashing at that one board matter more than anything else in the build.

East Hill ground perches water on hardpan

The hills either side of the valley are glacial till, and the USDA's description of the Alderwood soil that covers much of this kind of ground in the Puget lowland is the deck builder's problem in one sentence: moderately well drained, with a dense cemented layer 20 to 40 inches down and a perched water table above it from December through April. A post on a shallow pad in that ground stands in water four months a year. A footing to solid bearing and a standoff base above the concrete is how a frame here stays dry at the bottom.

The valley floor is soft and close to the water table

Down in the Green River valley the soil is river silt, deep and slow-draining, and the Howard Hanson Dam has kept the floods off it since 1962 without changing what it is. Footings there are sized for weaker bearing, usually a wider pad, and a ground-level deck needs a real gap under it so air moves. A platform on sleepers over damp silt grows moss on its underside before its top.

Signs a Kent Deck Is Past Repair

• Boards that give underfoot near the house wall or at the bottom of the stairs.
• A screwdriver that sinks into a joist from below. By the time rot shows on top it is usually already in the frame.
• The ledger dark, swollen, or pulling away from the house, or soft siding above it. This is the failure that drops decks.
• Posts green at the base, sitting in soil or in a concrete collar with no standoff.
• A guard that moves when leaned on, or balusters you can lift out by hand.
• Fasteners rusted through or popped, common on decks built before hot-dip galvanized hardware was standard with treated lumber.

One soft board on a tight deck is a repair. Rot in the ledger or several joists is a replacement, and money spent patching around it does not carry over to the new frame.

Get a Quote From a Licensed Kent Deck Builder

Describe the deck you want, or the one that is failing, and a licensed contractor serving Kent and south King County will call to arrange a site visit and quote.