Renovation Services
Deck Building
Custom decks engineered for Seattle's rain and lifestyle — beautiful materials, smart drainage, built to last decades.
Get a Free EstimateSeattle Deck Specialists
Outdoor Living, Built for the PNW
Seattle summers are stunning — and the right deck maximizes every warm day. But Pacific Northwest weather demands more than a standard deck build. Moisture, rain, and temperature swings require materials and construction methods specifically chosen for our climate.
Ergo Construction builds decks designed to survive Seattle weather for decades. Every deck we build includes proper drainage slope, moisture-resistant fasteners, and materials selected to prevent rot, warping, and premature failure.
Before, During & After
See the full transformation — from old structure to finished custom deck.
What's Included
Everything you need for a deck built right the first time.
Custom Design & Planning
We design decks that complement your home's architecture and maximize your outdoor living space.
PNW-Rated Materials
Composite decking, tropical hardwoods, and pressure-treated lumber selected for Seattle's rain and moisture.
Drainage & Moisture Protection
Built-in slope, hidden fasteners, and under-deck drainage systems that prevent rot and water damage.
Railings, Stairs & Lighting
Code-compliant railings, step lighting, and staircase designs for safety and curb appeal.
Permit-Ready Construction
We handle all Seattle and King County deck permits — proper footings, inspections, and code compliance.
Multi-Level & Elevated Decks
Complex multi-level designs, elevated decks with proper post and beam engineering.
Our Deck Building Process
Permitted, engineered, and built to Seattle code.
Site Assessment
We evaluate your yard, existing structure, soil, and grade to determine the best deck design and foundation approach.
Design & Quote
We create a deck plan with material options and provide a full itemized estimate before any work begins.
Permits
We submit plans to the City of Seattle or King County and coordinate all required inspections.
Foundation & Framing
Concrete footings, post installation, and structural framing — built to pass inspection and last for decades.
Decking & Finish
Decking boards, railings, stairs, lighting, and final inspection. We don't leave until everything is perfect.
Frequently Asked Questions
Do I need a permit to build a deck in Seattle?
Yes — any deck over 30 inches above grade or attached to the house requires a building permit in Seattle. We handle all permitting, inspections, and code compliance so you don't have to.
What decking material is best for Seattle?
Composite decking (Trex, TimberTech) is our most popular choice for the PNW — it resists moisture, doesn't splinter, and never needs staining. We also install pressure-treated lumber and tropical hardwoods for clients who prefer natural wood.
How long does a deck build take?
A standard single-level deck typically takes 1–2 weeks to build after permits are approved. Multi-level or complex designs can take 2–4 weeks. Permit approval times vary by project scope.
What does a deck cost in Seattle?
Deck pricing depends heavily on size, material, and complexity. A basic pressure-treated deck starts around $8,000–$15,000. A composite multi-level deck can run $25,000–$50,000+. We provide detailed, itemized estimates.
Ready to Build Your Dream Deck?
Get your free, no-obligation estimate. We respond within 24 hours.