Deck Building Cost in Seattle (2026)
Average cost in Seattle
US$6,500 — US$60,000
US$45 — US$180 per sq ft
Cost Breakdown
ItemizedLicensed deck contractors ($60-$100/hr)
45%
Lumber, composite boards, and hardware
35%
Seattle combined sales tax (10.35%)
10%
SDCI building permits and 18% YOY fee increase
6%
Demolition, hauling, and moisture protection
4%
Sales Tax at 6.5%
📋What's Included
ScopeTypically Includes
- Pressure-treated lumber
- Concrete footings
- Railing system
- Stairs (1 set)
- Hardware & fasteners
- Labor
Typically Excludes
- Composite or hardwood decking
- Built-in seating or planters
- Pergola or roof
- Lighting
- Permits
Based on a standard 200 sq ft pressure-treated wood deck.
🧮Estimate Your Cost
InteractiveEstimated Cost
US$6,800 — US$10,200
Based on 9 sources and market data for Seattle. Actual costs may vary depending on specific project requirements.
📈Price Momentum
Year-over-year~1 year ago
US$21,613
Today
US$23,450
Deck Building in Seattle is ↑ 8.5% compared to roughly a year ago — about US$1,837 more on the average project.
Comparison derived from the year-over-year change rate, not a month-by-month price index. We don't store historical snapshots yet — when we do, this will become a real time series.
🏢Top Deck Build Contractors in Seattle
Verified providersArchadeck of Seattle Eastside
410 Bellevue Way SE Suite 2, Bellevue, WA 98004, USA
81 reviews
Provider data sourced from public business directories. Ratings and reviews are public and may change. LookupCost is not affiliated with listed providers.
💬What People Actually Paid
Community❓Common Questions
Yes, the Seattle Department of Construction and Inspections (SDCI) requires a permit for any deck more than 18 inches above the ground, all roof decks, and decks in environmentally critical areas. A standard building permit for a deck project typically costs around $1,058.60 in 2026.
In 2026, Western Red Cedar costs approximately $60–$90 per square foot installed, while premium composite materials like Trex or TimberTech range from $80–$130 per square foot. While composite has a higher upfront cost, it is often preferred in Seattle's wet climate due to lower maintenance requirements.
Professional deck contractors in the Seattle and Puget Sound region typically charge between $60 and $100 per hour. Labor generally accounts for 40% to 60% of the total project cost due to the complexity of local terrain and strict seismic building codes.
Seattle has a high combined sales tax rate of 10.35%, which applies to both materials and labor for construction services. For an average $18,500 deck project, homeowners should budget approximately $1,914 specifically for sales tax.
📊Our Methodology
How we collect dataAggregated from 5+ verified web sources and cost databases
Licensed contractor estimates and regional cost guides
Government construction and labor statistics
Community-reported project costs and reviews
Last data collection: 4 days ago. Updates run weekly. All costs in USD.
About this data
Cost figures are estimates synthesized from public market data using AI research and refreshed regularly. Real project costs vary by scope, materials, contractor, and site conditions. Always get verified quotes from licensed contractors for your specific project.
Spotted bad data? Let us know — we'll review and update.