Composite Decking vs Wood Decking: Costs, Care And Lifespan

Choosing between composite decking vs wood decking is one of the biggest decisions you'll face when planning a new deck. Both materials have loyal advocates, and both come with real trade-offs in price, upkeep, and how long they'll actually last under Pacific Northwest weather. The right pick depends on your budget, your tolerance for maintenance, and how many years you expect that deck to serve your household.

At Legacy Exteriors LLC, we build custom decks across Kirkland, Bellevue, Redmond, and the surrounding areas, and we've installed plenty of both composite and wood. That hands-on experience has given us a clear picture of how each material performs once it's actually in place and exposed to our region's rain, temperature swings, and UV exposure. We don't push one option over the other; we help homeowners understand exactly what they're signing up for with each choice.

This guide breaks down the real costs (upfront and long-term), maintenance demands, and expected lifespan of composite and wood decking so you can make a confident decision before your project starts. We'll cover what matters and skip the filler, let's get into it.

What composite and wood decking are

Before you can weigh composite decking vs wood decking, you need a clear picture of what each material actually is. These aren't just two versions of the same thing with different price tags. They're built differently, behave differently, and require a different mindset from the homeowner who maintains them.

What composite decking is

Composite decking is an engineered building material made from a blend of wood fibers and recycled plastics, bound together with adhesives and formed into planks. Manufacturers cap most composite boards with a protective outer shell that resists moisture, fading, and surface scratches. Brands like Trex, TimberTech, and Fiberon dominate the market, and each offers multiple product lines ranging from entry-level to premium.

The protective cap layer on composite decking is what separates a board that holds up for 25 years from one that starts looking worn in five.

Because composite is a manufactured product, the quality varies significantly between brands and product tiers. A budget composite line may lack a full cap, leaving the wood-fiber core exposed on the sides and bottom, which invites moisture and mold over time. When you're comparing options, ask specifically whether the board is capped on all four sides.

What wood decking is

Wood decking is cut directly from natural timber, and the species you choose shapes everything from cost and hardness to how it responds to moisture. Pressure-treated pine is the most common and affordable option. Cedar and redwood offer natural resistance to decay and a warmer visual tone. For homeowners who want a premium hardwood look, tropical species like ipe or tigerwood deliver exceptional density and durability, though at a much higher price point.

Wood is a living material that expands and contracts with seasonal moisture changes. That movement is predictable and manageable when the deck is properly installed and sealed, but it's a factor you need to account for from the start. Each species has its own maintenance schedule, and skipping it shortens the life of your investment considerably.

Why your decking choice matters in Washington

Washington's climate puts a specific kind of stress on outdoor surfaces. The combination of heavy seasonal rainfall, extended gray periods, and summer UV exposure creates conditions that separate a well-chosen deck material from one that deteriorates in just a few years. When you're weighing composite decking vs wood decking, the Pacific Northwest context changes the math significantly compared to drier regions.

Rain and moisture exposure

Western Washington averages over 37 inches of rainfall per year, with the wettest months running from October through March. That sustained moisture penetrates untreated or under-sealed wood, accelerating rot, warping, and mold growth. Composite decking handles standing water much better because the capped surface blocks moisture from reaching the wood-fiber core. If you choose wood, the species and sealing schedule you commit to will determine how well it survives those wet months.

Kirkland and Bellevue homeowners often underestimate how quickly an improperly sealed wood deck can show signs of rot after just one or two wet seasons.

Temperature swings and UV

Summer in the greater Seattle area brings real UV exposure and temperature spikes that fade and dry out wood surfaces. That cycle of wet winters and sun-heavy summers causes significant expansion and contraction in natural timber. Composite boards are manufactured to handle that movement with less surface cracking, which is a meaningful advantage given how often Washington flips between those two extremes.

How to compare upfront and lifetime costs

When weighing composite decking vs wood decking, most homeowners look at material price first. That number matters, but stopping there gives you an incomplete picture of what you'll actually spend over the life of your deck.

Upfront material and installation costs

Wood decking, particularly pressure-treated pine, typically runs $15 to $25 per square foot installed in the Seattle metro area. Cedar and redwood push higher, and tropical hardwoods like ipe can exceed $40 per square foot. Composite decking starts around $25 to $35 per square foot for entry-level lines and climbs to $50 to $70 for premium capped products. If your budget is tight right now, wood gives you more deck for less money upfront.

Material	Installed cost per sq ft
Pressure-treated pine	$15 - $25
Cedar or redwood	$25 - $40
Composite (entry-level)	$25 - $35
Composite (premium capped)	$50 - $70

Long-term cost of ownership

Where wood loses ground is ongoing maintenance. Sealing or staining a wood deck every one to three years costs between $500 and $1,500 per cycle depending on your deck size and product choice. Composite requires almost none of that recurring spend, which means the cost gap between the two materials narrows steadily with each passing year.

Over a 20 to 25-year lifespan, many homeowners find that composite costs less in total than a wood deck that was cheaper to build.

Your best move is to calculate both the build cost and the expected maintenance cost together before committing to either material.

How to maintain composite and wood decks

Maintenance is where composite decking vs wood decking splits most sharply in practice. Wood demands a recurring schedule that costs both time and money, while composite cuts that burden down significantly. Knowing what each material needs before you build helps you plan your actual ownership experience, not just your build budget.

Maintaining a wood deck

Wood decks require sealing or staining every one to three years to stay protected against moisture, UV damage, and surface cracking. Before each application, you need to clean the surface, sand any rough or raised grain, and let the boards dry completely. Skipping even one maintenance cycle in a wet Washington climate can allow moisture to penetrate and start rot from the inside out, which shortens the deck's usable life fast.

Missing a single sealing cycle on a wood deck in western Washington can set off a chain of damage that takes far more than a tube of sealant to fix.

Maintaining a composite deck

Composite decking asks very little from you on a regular basis. Sweeping off debris and rinsing the surface a few times per year is enough for most installations. Pollen, leaf tannins, and mildew can leave staining if left to sit, so a mild soap and water scrub in spring and fall keeps the boards looking clean. You won't need to sand, stain, or seal composite boards at any point during their lifespan.

Lifespan and durability in Pacific Northwest weather

When you stack composite decking vs wood decking on lifespan alone, composite has a clear edge in Washington's conditions. Premium capped composite boards carry manufacturer warranties of 25 to 30 years, and they typically reach that mark without major structural issues because the capped surface resists the moisture and UV cycles that wear wood down season after season.

How long wood decks last here

A well-maintained pressure-treated pine deck lasts 15 to 20 years in western Washington, assuming you keep up with sealing and address any soft spots early. Cedar and redwood perform similarly when properly cared for, while tropical hardwoods like ipe can stretch beyond 25 years given their natural density. The catch is that every year you skip maintenance, you're cutting time off that projection.

A wood deck that misses two or three sealing cycles in a row can lose a decade of useful life in Washington's wet climate.

How long composite decks last here

Composite boards hold up consistently across the wet season and dry season cycle without demanding anything from you in return. The capped surface resists surface checking, fading, and mold growth far better than natural timber. Most mid-to-premium composite products installed correctly will outlast a wood deck by five to ten years in this region, making them a strong long-term bet for homeowners who plan to stay in their home and want to avoid repeated maintenance costs.

Wrap-up and next step

The composite decking vs wood decking decision comes down to three things: what you can spend upfront, how much time you want to spend on maintenance, and how long you plan to stay in your home. Wood costs less to build but demands more from you every year. Composite costs more at the start but pays that back steadily through lower maintenance and a longer usable lifespan, especially in western Washington's wet climate.

Neither material is wrong. Both build a functional, attractive outdoor space when installed correctly and maintained appropriately. Your specific budget, timeline, and lifestyle should drive the final call, not a blanket recommendation from someone who hasn't seen your property.

If you're ready to move forward, Legacy Exteriors LLC builds custom decks across Kirkland, Bellevue, Redmond, and the surrounding areas. Request a free deck quote and we'll walk you through your options with a locked-in price before any work begins.