Decks contractor —
Seattle & Puget Sound.
Most deck failures trace back to the ledger board. We bolt to engineered standards, flash the ledger correctly, and pour foundations sized for our soils.
Most deck failures trace back to the ledger board — the connection between deck and house. The 2008 IRC tightened ledger requirements, but pre-2008 decks across Seattle were attached with nails into rim joists, often without flashing. We replace ledgers to current spec on every retrofit.
Composite decking (TimberTech, Trex, Fiberon) is the right choice for 80% of new decks. It survives PNW moisture without staining, holds color, and works with hidden fastener systems for a clean surface. Ipe and cedar are for the projects where natural-wood character justifies the 5–7 year refinish cycle.
What we build
SCOPE- 01Engineered ledger connection
- 02Composite + hardwood decking
- 03Hidden fastener systems
- 04Cable + glass railings
- 05Cantilevered + multi-level
- 06Integrated lighting + drainage
Phased process
PROCESS- 01
Design + permit
Engineered plans for any deck over 30" above grade or attached to house. Permit through SDCI or county AHJ.
- 02
Foundation
Concrete footings to frost depth (typically 12" in lowland PNW, 18" in higher elevations), sized for column load.
- 03
Ledger + structure
Engineered ledger connection with through-bolts and proper flashing. PT framing (2× joists, blocking, beams) to engineer's drawings.
- 04
Decking install
Composite or hardwood decking with hidden fastener system, proper gap for thermal expansion.
- 05
Railings
Code-compliant 36" or 42" railing (per deck height), cable, glass, or aluminum picket systems.
- 06
Finish + inspection
Stair treads, lighting integration, drainage detailing, final building inspection.
Spec sheet
SPEC- +TimberTech AZEK or Trex Transcend composite decking (capped polymer)
- +Ipe, mahogany, or western red cedar for natural-wood decks
- +Hidden fastener system (Camo, Cortex, or Tiger Claw)
- +Pressure-treated framing (PT 2× joists at 16" OC, doubled or LVL beams)
- +Cable railing (Atlantis, Feeney), glass panel, or aluminum picket
- +Trex RainEscape under-deck drainage system for dry space below
- +Low-voltage LED stair and rail lighting on dedicated transformer
Cost drivers
COST- Decking materialPT lumber $8–$12/sf → composite $25–$45/sf → ipe $40–$70/sf installed
- Deck height + railings30"+ above grade triggers railing code; cable + glass +$80–$220/lf
- Multi-level / cantilever+$8K–$25K for engineering and additional framing
- Foundation typeHelical piers +$1,500–$4,000 vs poured footings on difficult soils
- Lighting and drainage upgrades+$3K–$12K for full integration
Codes & permits
COMPLIANCE- IRC R507 (decks)
Comprehensive deck code covering ledger connection, footing depth, joist span, and railing requirements. Permit required for decks >30" above grade.
- DCA 6 (Prescriptive Deck Guide)
Engineered span tables and connector specs. We design to DCA 6 unless project complexity warrants custom engineering.
- Seattle ECA (Environmentally Critical Area)
Decks in steep-slope or wetland buffers require additional environmental review. We screen during feasibility.
Is decks the right call?
- →Replacing a deck older than 15 years (pre-2008 ledger connections are suspect)
- →Adding outdoor living space to a primary residence
- →Multi-level decks for sloped Seattle lots
- →Combining with patio cover or pergola for year-round use
Decks questions
FAQQ.01
How long does a composite deck last?
25–30 years for premium capped composite (TimberTech AZEK, Trex Transcend). The composite itself is functionally permanent; UV fade and hidden-fastener corrosion are the failure modes.Q.02
Do I need a permit?
Yes for any deck more than 30" above grade or attached to a house. Free-standing low decks are typically exempt but check your AHJ.Q.03
Composite vs hardwood — which is better in PNW?
Composite wins on maintenance — no staining, sealing, or color fade. Hardwood (ipe, mahogany) wins on natural character but needs annual oil and accepts gray patina if neglected. We default to composite for most clients.Q.04
Can you build a deck on a sloped lot?
Yes — multi-level decks with cantilevered sections, deep helical pier foundations, and engineered framing are our specialty in Seattle's hillside neighborhoods. Expect significant engineering and a longer permit timeline.
Official resources & sources
- Source ↗IRC R507 — Exterior Decks
- Source ↗WSEC 2021 Residential Energy CodeEnvelope, HVAC, hot-water and air-sealing requirements
- Source ↗WA HB 1110 — Middle housing lawStatewide middle-housing zoning preemption
- Source ↗WA HB 1337 — ADU statewide rulesTwo-ADU baseline, no owner occupancy, parking limits
- Source ↗WA Dept. of Commerce — ADU resources
- Source ↗WA L&I contractor license lookupVerify Golden State ADU Builders Inc · GOLDESA747LZ
- Source ↗Washington State Building Code CouncilStatewide adopted codes (IRC, IBC, WSEC)
Ready to scope your decks project?
Send a paragraph and the address. A licensed PM replies within one business day with next steps.
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