Western Red Cedar
Warm, natural, PNW-native. Beautiful and mid-priced — needs sealing every few years to fight our moisture.
Sealing & waterproofing Seattle & the Eastside
The maintenance that doubles a deck’s life
In our climate an unsealed deck soaks up water nine months a year. Sealing and waterproofing is the cheapest thing you can do to fight moss, cupping and rot.
5.0
★★★★★
29+ reviews
5.0
★★★★★
31+ reviews
10 years
Workmanship warranty
12 years
Building in Seattle
300+
Decks Built & Restored
What we protect
Stop the water before it costs you a rebuild
Water is what kills Seattle decks. We clean, prep and seal the surface, then treat the problem spots — so your deck sheds our rain instead of soaking it up.
- Deep clean, moss and mildew removal
- Commercial-grade penetrating sealants
- Crack, gap and fastener treatment
- Re-seal schedule so protection lasts
Elevated & roof decks
Under-deck drainage & membrane systems
For elevated decks and roof decks, waterproofing isn’t optional — it protects the living space below. We install under-deck drainage and membrane systems that keep everything beneath bone dry.
- Under-deck drainage to create dry space below
- Membrane waterproofing for roof decks
- Proper flashing at walls and posts
- Keeps framing — and rooms below — dry year-round
Before & after
From mossy and soaked to sealed and dry
A proper clean-and-seal changes how a deck looks — and how long it lasts.
Choose with your eyes open
The right material for your budget, your look, and our rain
We walk you through the trade-offs honestly — no pushing the priciest option. Here’s the short version.
Composite
Near-zero maintenance and rot-proof — ideal for rain. Higher upfront cost, lower cost over its life.
Hardwood (Ipe)
Premium, dense, decades-long lifespan. A statement surface for homeowners who want the very best.
Free 3D visualization
See your dream deck before we build it
Every full deck build includes a professional 3D visualization — so you know exactly what you're getting before construction begins
Included with every deck we build
Schedule Your Free Estimate
12 Years building in Seattle
Seattle’s deck specialists
A family business, built on the work — not the sales pitch
Craft Boys started with two brothers, a truck, and a refusal to cut corners. Today we’re a licensed, insured, Google Guaranteed team that Seattle homeowners trust with their hardest outdoor projects.
We take on the work others pass on, and we stand behind every job with a 10-year workmanship warranty and free follow-up inspections.
Listen to our story
1:30
The Craft Boys family
Recent work
Decks we’ve sealed & waterproofed
Go behind the finish. We open up one complete Seattle project—drawings, materials, quality checks, and the hidden work most builders never show you.
Two decks, rebuilt from the footings up
Bellevue, WA
Two elevated decks on a sloped lot, taken down to the footings and rebuilt — new pressure-treated frames, composite tops, and railings brought back to life, all within the original footprint.
Explore projects
A small deck, rebuilt bigger — then a patio to match
Redmond, WA
A cramped 8×10 deck torn down and reimagined as a larger 12×14 — new frame, composite decking and railings, and a composite privacy screen for a corner that finally feels private. Six months later, they brought us back for a 1,000 sq ft tile patio.
Explore projects
Real reviews, real clients
All reviews
5.0
What clients consistently say
Across 50+ reviews, homeowners highlight precise craftsmanship, on-time crews that clean up daily, honest pricing with no surprises, and decks that feel solid and safe — even on complex, multi-level builds.
James Blair
Magnolia, Seattle May 2026
Craft Boys rebuilt our two-tier deck on a sloped backyard that three other contractors refused to touch. Engineered drawings, permits, hidden fasteners — everything done right, on schedule, and the crew cleaned up every single evening.
Rachel Kim
Bellevue April 2026
We got quotes from five companies and Craft Boys was the only one that explained WHY the old deck failed. New composite deck with cable railings is stunning, and the price matched the written estimate to the dollar.
Michael Torres
Kirkland March 2026
Our 20-year-old cedar deck looked done for. They restored it — sanded, re-stained, replaced the bad boards — for a third of what a rebuild would cost. Honest advice instead of an upsell. Rare these days.
Elena Petrov
Sammamish February 2026
Pergola + deck extension finished ahead of schedule despite the February rain. The crew tarped everything daily and the site was spotless. The 3D visualization beforehand made every decision easy.
David Chen
Mercer Island January 2026
Second project with Craft Boys — deck repair after a winter leak, then full waterproofing with an under-deck drainage system. Their 10-year warranty is real: they came back for the free follow-up inspection unprompted.
Sarah Mitchell
Redmond May 2026
Found them on Thumbtack, best decision of our remodel. They replaced rotten joists other companies missed and finished the new decking so cleanly you can't find a visible screw. Communication was instant.
To guarantee the highest quality, we accept only 3 projects per month.
Availability right now:
July
August
September
Book your free estimate
Pick a day and time that works — we'll confirm within 2 hours.
Financing available
Your dream deck, on a plan that fits your budget.
We've partnered with GreenSky® — one of the most trusted names in home-improvement lending — so qualified homeowners can finance their project with simple, flexible monthly payments.
No need to drain your savings or put off the build. Apply in minutes, get a fast decision, and start sooner.
Check Your Financing Options
Before you ask
Sealing & waterproofing, answered
The questions Seattle homeowners ask us most — answered the way we answer them on site.
In our wet climate, roughly every two to three years for most decks — sooner for high-traffic or fully-exposed ones. We leave you a simple schedule.
Sealing protects the wood surface from moisture and UV. Waterproofing (drainage and membranes) keeps water from passing through an elevated or roof deck to the space below. Many decks want both.
Yes — an under-deck drainage system channels water away and turns the space below an elevated deck into dry, usable storage or a covered patio.
No — sealing prevents rot, it doesn’t cure it. If there’s existing rot we repair it first, then seal so it doesn’t come back.
Composite doesn’t need sealing, but it does benefit from cleaning and moss treatment. We’ll tell you honestly what your deck actually needs.
Free estimate
Protect the deck you already own
Tell us about your deck — we’ll confirm a visit within 2 hours. No obligation, no pressure.
Free safety checklist
Why we made this guide: so you don't pay twice
We've seen it too many times—homeowners hire the cheapest contractor, then call us a year later to rebuild what should've been done right the first time. So we wrote down everything we know.