Deck Building Cost in Washington (2026)
Deck Building in Washington runs about 15% above the national average. A typical 320 sq ft project starts around $5,520–$9,200 for pressure-treated wood. Estimate your exact project below.
Deck Building Cost Calculator
Adjust the details for an installed-cost range tailored to you.
Length × width of the deck surface. A 16×20 deck is 320 sq ft.
Ballpark estimate for planning — not a quote.
Get your exact price from local deck pros
This is a ballpark — compare up to 3 free, no-obligation quotes from vetted contractors in Washington.
Deck Building cost in Washington by material
Installed cost for a typical 320 sq ft project in Washington.
| Material | Per sq ft | Typical WA project |
|---|---|---|
| Pressure-treated wood | $17.3–$28.7 | $5,520 – $9,200 |
| Cedar / redwood | $28.7–$46.0 | $9,200 – $14,720 |
| Composite (Trex-style) | $34.5–$69.0 | $11,040 – $22,080 |
What affects your Washington cost
- Decking material and railing style
- Height off the ground and stairs
- Footings, framing and permits
- Built-ins (benches, pergola, lighting)
- Local labor rates
Washington deck building — FAQ
How much does deck building cost in Washington?
In Washington, a typical 320 sq ft deck building project runs about $5,520–$9,200 for pressure-treated wood, installed. That's about 15% above the national average. Higher-end materials cost more — use the calculator above for your exact size and material.
How much does deck building cost per sq ft in Washington?
In Washington, installed deck runs about $17.3–$69.0 per sq ft depending on material (pressure-treated wood $17.3–$28.7, cedar / redwood $28.7–$46.0, composite (trex-style) $34.5–$69.0). That's about 15% above the national average.
How much does it cost to build a deck in 2026?
A typical 320 sq ft deck runs about $5,000–$8,000 in pressure-treated wood, or $10,000–$19,000 in composite, installed. Size, height, railings and material drive the price — use the calculator for a localized estimate.
Is composite decking worth it?
Composite costs roughly 1.5–2× wood up front but eliminates staining/sealing and lasts 25–30+ years, so total cost of ownership is often lower. It's the popular choice for homeowners who don't want annual maintenance.