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How much does a 400 sq ft deck cost in Tri-Cities, WA?

A pressure-treated deck build in Tri-Cities, WA
$14,698
400 ft² of deck · typical range $11,135 – $22,269
Typical total$37 per ft² of deck$14,698
Range you should see in bidsthree bids on the same scope normally land inside this$11,135 – $22,269
Labor portion55% of the job — this is the part that moves by city$8,084
Material portion45% — bought at national prices$6,614
Carpenters pay near Tri-CitiesBLS does not publish a metro figure for carpenters near Tri-Cities, WA, so this is the Washington state average, SOC 47-2031$79,170/yr
U.S. mean for the same tradeSOC 47-2031$65,630/yr
Versus the national pricetrade pay here runs +20.6% against the U.S. mean+$1,498

Notes

  • Where the number comes from. The national price for a pressure-treated deck build is $33 per ft² of deck — pressure-treated deck pricing published for 2026, $25–$50 per ft² installed. Labor is about 55% of that. Carpenters near Tri-Cities, WA average $79,170 a year against a U.S. mean of $65,630 — a factor of 1.206 — so the labor half is scaled by that and the material half is not. Source: BLS does not publish a metro figure for carpenters near Tri-Cities, WA, so this is the Washington state average, SOC 47-2031.
  • This one falls back to a wider average. BLS did not publish a metro-level wage for this trade near Tri-Cities, WA, so the figure above is a state average. It is still the right order of magnitude, but a local bid carries more weight here than it would in a large metro where the survey has more responses.
  • What is in the price: footings, framing, pressure-treated decking, fasteners, a code-compliant railing, and labor.
  • What is not: stairs beyond two steps, permits, ledger repair on the house, and any grading work. These are the lines that turn a $14,698 quote into a $18,372 invoice, so ask about each one before signing.
  • Use this as a bid check, not a quote. It prices an average job in average condition. Difficult access, the state of what is being replaced, the season, and a crew booked out three months all move the real number, and none of them are in a per-unit average.

a pressure-treated deck build in Tri-Cities, WA

$14,698 is the typical number, and three bids on the same scope normally land between $11,135 and $22,269.

That is $1,498 more than the same job priced at the national average.

Why the city changes the number

About 55% of this job is labor — $8,084 of the $14,698 above. Labor is the only part that moves locally; a bundle of material costs what it costs wherever it is nailed down.

Carpenters near Tri-Cities average $79,170 a year, against a U.S. mean of $65,630. That is a factor of 1.206, so the labor half is scaled by it and the material half is not.

Source: BLS does not publish a metro figure for carpenters near Tri-Cities, WA, so this is the Washington state average, SOC 47-2031.

What the quote should include

The lines that turn a quote into an invoice

Ask about each of them before you sign. On a job this size they are the difference between $14,698 and something a quarter higher.

Use it as a bid check, not a quote

This prices an average job in average condition. Access, the state of what is being replaced, the season, and a crew booked out three months all move the real number, and none of them are in a national average.

If a bid lands outside $11,135 – $22,269, that is not automatically wrong — but it is the question worth asking out loud.

Nearby sizes

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