Whether you're building a new deck or replacing one that's rotted out, Left Coast Exteriors brings structural experience and composite material expertise to every project. We're a TimberTech and Fiberon authorized installer.
TimberTech & Fiberon Authorized
Pressure-treated lumber was the standard for decks in the Pacific Northwest for decades, and it still has its place. But in Clark County and the broader Camas, Washougal, and east Clark County corridor, where homes see extended wet seasons, significant tree canopy keeping surfaces damp, and freeze-thaw cycling from the Columbia River Gorge, pressure-treated decking has a demanding service life. It splits, grays, and begins to cup and check within a few years without consistent sealing. The maintenance cycle never ends: clean, sand, seal every 2–3 years or watch it degrade faster. Most homeowners underestimate how quickly that adds up.
Composite decking eliminates that cycle entirely. High-quality capped composites like TimberTech AZEK and the TimberTech Pro Legacy Collection don't absorb moisture, don't gray, don't split, and don't require sealing. Ever. The cap layer protects the core material from the surface in, and in a climate where mold and mildew pressure are real, a capped composite with UV-stable pigments will look almost identical in year fifteen as it did at installation. For a lakeside property in Washougal, a Gorge-corridor home that takes wind and rain from the east, or simply a homeowner who is done spending weekends maintaining a pressure-treated deck, composite is the right answer.
The long-term financial case is straightforward. Composite decking costs more upfront than pressure-treated. But when you account for the elimination of staining and sealing costs, the extended lifespan (25–30+ years vs. 10–15 for maintained PT in Northwest conditions), and the impact on home value, the total cost of ownership comparison shifts significantly. Composite decks also carry transferable limited warranties from TimberTech and Fiberon, a tangible selling point when it's time to list the home.
Whether you're starting from scratch or tearing out a failing pressure-treated deck, we'll help you make the right call for your home and budget.
We install TimberTech, Fiberon, and traditional pressure-treated wood decking. Most homeowners choose composite, but we'll give you an honest comparison so you can make the right call for your home, your climate exposure, and your budget.
AZEK is fully capped cellular PVC. No wood fiber composite, no organic content. That means zero moisture absorption and the highest moisture resistance available in the decking category. It won't warp, won't grow mold, and won't stain from organic matter the way composites can in shaded, wet environments. Ideal for lakeside and waterfront installations in Washougal and along the Columbia, for homes with heavy canopy cover, or for any homeowner who simply wants the absolute lowest-maintenance option available. Backed by TimberTech's 50-year limited fade and stain warranty.
The Pro Legacy Collection is our most frequently recommended product for Clark County residential decks. It's a fully capped wood-composite that delivers the warm, natural wood aesthetics that most homeowners want, with composite performance that eliminates the maintenance cycle. Four-sided capping protects the core from all sides, including the ends, which is where uncapped composites absorb moisture and fail first in wet climates. Available in a wide range of wood-tone colors and complementing railing options. TimberTech Pro carries a 25-year product warranty and a 25-year fade and stain warranty.
For homeowners who want composite performance at a lower upfront cost, the Fiberon Pro-Tect Advantage is a solid choice. It's a capped composite with good moisture and stain resistance, suitable for standard Pacific Northwest residential deck applications. It won't match the longevity or warranty depth of AZEK or the Pro Legacy Collection, but it's a meaningful upgrade over pressure-treated in any wet-climate environment. Good option for homeowners replacing a smaller deck, managing a tighter project budget, or building a secondary structure like a landing or lower tier where the premium product isn't necessary.
Pressure-treated wood remains a legitimate option for homeowners with a tighter upfront budget, those planning to sell in the near term, or those who genuinely prefer natural wood. We use #2 or better Southern Yellow Pine treated to UC4B spec for ground-contact applications, the right grade for the structural and ledger members that every deck requires regardless of decking material. As a surface decking choice, PT wood will require staining or sealing every 2–3 years in Pacific Northwest conditions to stay ahead of graying, checking, and splinter development. If you're committed to that maintenance cycle, or if budget is the primary constraint, we'll build it right. If you want to eliminate the maintenance cycle, composite is the better long-term value, and we'll show you the math either way.
We're authorized installers for both TimberTech and Fiberon, the two premier composite decking brands in the Pacific Northwest. Authorization means we install to full manufacturer spec, which is what activates the 25–50 year product and fade/stain warranties. We're not just reselling boards: we're accountable for the installation quality that makes the warranty real.
A lot of deck replacements in the Pacific Northwest involve rotted ledger boards, failed post bases, or compromised joists that get covered over rather than replaced. We inspect every element of your existing substructure before we recommend what to reuse, and we document what we find so you understand exactly what you're getting.
Decks require structural permits in Clark County. We handle the permit application, engineer the ledger connection and post sizing to code, and schedule the required framing inspection. A properly permitted deck protects your homeowner's insurance, your home sale, and anyone who stands on it.
A deck project involves structure, permits, and a lot of decisions before the first board goes down. Here's how we handle it.
We come to your property and assess the existing structure (if there is one), the site conditions, grade, access constraints, and what you're trying to accomplish. For replacements, we evaluate the ledger connection, post footings, and framing to determine what can be retained and what needs to be rebuilt. You get a realistic assessment before we quote anything.
We work through the deck layout, dimensions, elevation, and railing details with you. We present the product options that fit your project and make a recommendation based on your site's exposure, your maintenance preferences, and your budget. Written, itemized estimate covers decking, framing, hardware, railing, and labor, line by line.
We prepare and submit the permit application with Clark County or the relevant jurisdiction, including the required structural drawings. Once the permit is issued, we schedule your build. Most deck permits in Clark County are issued within 2–3 weeks for standard residential projects.
Demo of the old structure (if applicable), footing inspection or new footing installation, ledger installation with proper flashing, framing to code, composite decking installation, and railing installation, all by our in-house crew. We don't subcontract the framing and hand off the decking. The same crew handles the complete structural scope.
We do a complete final inspection with you before we consider the project done. We walk the structure, demonstrate railing stability, and make sure every detail is finished to your satisfaction. We coordinate the final permit inspection with the county and provide you with all warranty documentation from TimberTech or Fiberon.
Deck replacement costs vary significantly based on deck size, the extent of framing replacement needed, the composite product tier selected, and railing choices. A straightforward 300 sq ft deck replacement with TimberTech Pro Legacy Collection decking and standard aluminum railing will typically run $18,000–$28,000 in Clark County. Larger decks, custom railing systems, or premium AZEK material will be higher. We provide complete itemized written estimates, framing, decking, hardware, railing, permit, and labor broken out separately, so you know exactly what you're approving.
Yes. In Clark County, any deck 30 inches or more above grade requires a building permit. This includes replacements of existing permitted structures. The permit process requires a structural plan review and inspection at multiple stages, including footing inspection before concrete is poured and framing inspection before decking is installed. Decks built without permits create serious problems at resale. Title companies will flag unpermitted structures, and buyers or their inspectors will often request they either be permitted retroactively (difficult and expensive) or removed. We handle the permit as a standard part of every deck project.
In Pacific Northwest conditions, well-maintained pressure-treated decking typically lasts 10–15 years before it needs replacement, and "well-maintained" means regular cleaning, sealing, and prompt repair of any fastener or board issues. Without maintenance, that lifespan is shorter. Premium capped composite decking like TimberTech AZEK or Pro Legacy carries 25–50 year limited warranties and, in real-world Northwest conditions, routinely outlasts pressure-treated significantly. The board material itself won't rot, split, or gray. The framing underneath still needs to be pressure-treated lumber or a steel frame. Composite decking sits on top, it doesn't replace the structural members.
Yes, absolutely. New deck construction is a significant share of our deck work. We handle everything from the initial site assessment and layout through permit application, footing installation, framing, composite decking, and railing. New construction requires more planning than a replacement. We need to establish the right elevation, ensure the ledger connection to the house is flashed and fastened correctly, and design the footing layout to meet Clark County's setback and structural requirements. We'll work through those details with you during the consultation and site visit, and provide you with a permit-ready plan as part of the scope.
The answer depends on the condition of the framing underneath the decking. If the joists, beams, posts, and ledger are all structurally sound, no rot, no fastener corrosion, no movement, then decking-only replacement is a legitimate option and can save money. If the framing shows rot, if the posts are at or near grade (a moisture trap), if the ledger flashing was poorly done and there's moisture in the rim joist, or if the footings are inadequate, then you're rebuilding, not resurfacing. We assess the framing condition honestly during the estimate and give you a straight recommendation. We don't push full rebuilds on sound framing, and we don't recommend board replacement on compromised structure.
Yes. We offer flexible financing through third-party lenders with terms from 12 to 84 months and 0% intro APR options for qualified buyers. A composite deck replacement typically ranges from $12,000–$30,000 depending on square footage, product tier, and substructure condition. Financing spreads that over manageable monthly payments while you start enjoying the space immediately. Ask your project consultant about current programs when you receive your estimate.
We serve homeowners throughout Southwest Washington and the greater Portland area. View full service area →
"Our old pressure-treated deck was 18 years old and had been rotting in the back corner for two years. Left Coast came out, assessed the framing, and told us the ledger was fine but the joists on the low end were done. They gave us a clear scope: rebuild those joist bays plus full composite decking, and the project came in exactly as estimated. The TimberTech Pro Legacy looks incredible and I haven't touched it since. Not once."
"We had Left Coast build a brand new deck off the back of our home. Nothing was there before. They handled the permit from start to finish, which I was dreading dealing with. The footing layout, framing, and composite installation were all done in about a week. We went with AZEK because we have significant tree coverage and shade and they explained why the PVC product was the right choice for our exposure. The deck looks beautiful and the quality of the construction is obvious."
"We'd had our pressure-treated deck painted and sealed twice in six years and were done with the maintenance cycle. Left Coast replaced it completely with TimberTech Pro Legacy and new cable railing. The difference in how the back of our house looks is dramatic. The crew was respectful of the property the whole time, the project was done on the schedule they gave us, and the final walkthrough was thorough. Highly recommend them for anyone in the Washougal area."
Financing Available
A quality composite deck is a 25–50 year investment. We offer flexible financing so you can build the deck you actually want instead of compromising on size, materials, or features to fit a one-time budget.
Composite decks add significant resale value and eliminate the $500–$1,000 annual maintenance cost of pressure-treated wood.
Financing offered through third-party lenders. Subject to credit approval. Ask your project consultant for current terms and available programs.
Request a Free EstimateOther Services
