What's the actual difference between capped and uncapped composite decking?

Capped composite has a protective plastic shell wrapped around a wood-plastic core, which resists moisture, staining, and fading better than uncapped boards where the core is exposed at the surface. In a wet, moss-prone climate like this one, capped boards hold up noticeably better over time, though they typically cost more upfront.

How do I check that a contractor is actually licensed to do decking work in Washington?

Washington contractors carry a state contractor license number that you can look up directly through the Department of Labor & Industries website, which also shows bond and insurance status. Ask for that number before signing anything, and be cautious of anyone unwilling to provide it.

Does it matter which composite decking brand gets used?

It matters less than most marketing suggests — several major manufacturers produce solid, well-tested capped composite lines with comparable warranties. What matters more is correct installation: proper spacing, fastening, and substructure, since even a good board performs poorly if it's installed wrong.

Can composite decking be installed directly over an existing wood deck frame?

Sometimes, if the existing framing is structurally sound, properly spaced for composite, and free of rot — but it needs a real inspection first, not just a visual glance. In this climate, hidden moisture damage in older framing is common enough that we usually recommend opening it up to check before committing either way.

Does a deck near the Aldergrove–Lynden border area need different permitting than one further inland?

Permitting depends on which side of the border and which local jurisdiction the property falls under, not distance from the crossing itself, so requirements can differ between Whatcom County and Fraser Valley municipalities. We handle the Washington-side permitting process directly and can point Canadian-side homeowners toward the right local authority for theirs.

Composite Decking in Aldergrove, BC — Built by a Local Lynden Crew

Composite Decking for Aldergrove, BC Homes

Aldergrove sits right across the line from Lynden, close enough that a lot of homeowners there already know our trucks from jobs on the Washington side. The building style, lot sizes, and weather on both sides of the Aldergrove–Lynden crossing are close to identical, which means the same decking problems show up in both places: boards that cup and gray within a few seasons, railings that loosen from moisture cycling, and a surface that turns slick and green well before summer ends. Composite decking, installed correctly for this specific climate, solves most of that. This page covers what a composite deck actually needs to hold up in Aldergrove, BC, what we do differently because of the local weather, and why working with a crew that's already familiar with this specific corner of the border matters more than it sounds like it should.

What This Climate Actually Does to a Deck

Whatcom County and the Fraser Valley share the same weather pattern, and it's a tough one for outdoor wood surfaces. Three things do most of the damage:

Driving rain that gets under the surface, not just on it. Wind-driven storms push water sideways into board gaps, fastener holes, and end grain — areas that never dry out fully between systems.
A long moss and algae season. Cool, damp shade for much of the year means moss and algae get a head start every fall and don't fully die back until late spring, especially on decks with limited sun exposure or heavy tree cover.
Salt-tinged air moving in off the Strait and Sound. It's not coastal-strength salt exposure, but it's enough to accelerate corrosion on cheap fasteners, hinges, and railing hardware over years of exposure.

None of these individually ruins a deck fast. What they do is compound — wet wood stays wet longer, moss holds moisture against the surface, and corroding fasteners loosen boards that then trap even more water. A deck built without that cycle in mind ages years faster than it should.

Why Composite Holds Up Better Here

Composite decking is a blend of wood fiber and plastic, capped (in most quality lines) with a protective outer shell. It doesn't absorb water the way solid wood does, it doesn't need annual staining or sealing, and it doesn't provide the same food source for mold and algae that raw wood fiber does. That doesn't mean it's maintenance-free — we'll get into what it does need — but it removes the single biggest failure point in this climate: wood that stays damp for months at a time.

It's not automatically the right call for every homeowner or every budget, and we'll say so plainly if a project doesn't fit it. But for a deck that sees real Pacific Northwest weather and gets used year-round, it's the option that requires the least fighting against the climate.

Composite vs. Wood vs. PVC — How They Compare Locally

Factor	Pressure-Treated Wood	Composite	PVC / Vinyl
Moisture resistance	Low — absorbs and swells	High — capped boards resist water	Very high, fully synthetic
Moss/algae resistance	Poor without frequent cleaning	Good, easier to clean than wood	Good, similar to composite
Annual maintenance	Staining/sealing, sanding splinters	Occasional wash-down	Occasional wash-down
Upfront cost	Lowest	Mid-range	Highest
Look and feel underfoot	Natural, but inconsistent	Consistent, wood-grain texture available	Very uniform, plastic feel to some
Typical lifespan here	10-15 years before major repair	25-30+ years with proper install	25-30+ years

We install all three depending on the homeowner's priorities, but for this specific climate — long wet season, moss pressure, salt-tinged air — composite is usually the best balance of cost, appearance, and low maintenance. We'll talk through the honest trade-offs for your situation rather than push one product across the board.

What a Correctly Built Composite Deck Involves

Composite boards are only as good as what's underneath them. Most of the "composite decks fail" complaints we hear about trace back to substructure or fastening mistakes, not the decking material itself. A job done right includes:

Substructure and Drainage

Joist spacing has to match the manufacturer's spec for the specific board profile — composite boards flex differently than wood and are less forgiving of wide joist spacing over time. Ledger boards attaching to the house need proper flashing so water sheds away from the wall framing instead of into it, which matters a lot given how much rain this area sees in a typical winter. Ground clearance and airflow under the deck also need to be adequate; a deck built too close to grade traps moisture underneath even if the surface stays dry.

Fasteners and Hardware

Given the salt-tinged air along this stretch of the border region, we use corrosion-resistant, coated fasteners rated for treated lumber and composite contact — not standard hardware that looks fine going in but starts staining and weakening within a few years. Hidden fastener clip systems, when compatible with the board profile, also reduce the number of surface penetrations where water and grime can collect.

Board Layout and Expansion Gaps

Composite expands and contracts with temperature more than people expect. Gaps between boards, at butt joints, and around fixed obstructions like posts need to be sized correctly for the swing this climate produces across a full year — too tight and boards buckle in a hot stretch; too loose and it looks sloppy and traps debris.

Our Process, Start to Finish

On-site walkthrough. We look at the existing structure (if replacing a deck), grade and drainage around the footprint, sun exposure, and how the space actually gets used.
Honest product conversation. We show you a few composite lines that fit the budget and the look you want, and we're direct about which is overkill and which is a poor fit for a shaded, damp area.
Written estimate. Materials, labor, framing/substructure work, railing, and any structural repairs are itemized — no vague lump-sum guessing.
Framing and substructure. This is where most of the long-term durability gets decided, and we don't rush it.
Decking, fascia, and railing install. Board layout planned to minimize seams in high-visibility areas, proper gapping, and corrosion-resistant fastening throughout.
Final walkthrough. We go over care basics with you before we consider the job done.

Maintenance: What Composite Actually Needs Here

"Low maintenance" doesn't mean "no maintenance," especially with a moss season as long as this one. What actually keeps a composite deck looking right:

A wash-down with a soft brush and mild soap once or twice a year, more often on shaded sections that hold moisture longer
Keeping leaves and debris cleared out of board gaps before they compost in place, which is what actually feeds moss growth
Trimming back overhanging branches or shrubs that keep sections of the deck shaded and damp longer than the rest
Checking railing posts and fasteners annually for any looseness, since hardware is the first thing affected by the salt-tinged air here
Avoiding pressure washing at close range or high PSI, which can damage the cap layer on some board profiles

What Drives the Cost of a Composite Deck

We don't quote firm numbers on a page like this — every project is different — but these are the factors that move the price up or down, in rough order of impact:

Factor	Why It Matters
Square footage and deck shape	More cuts, angles, and picture-framing add labor beyond straight material cost
Substructure condition	Reusing sound existing framing costs less than a full rebuild from the ground up
Board tier	Entry-level capped composite vs. premium wood-grain or multi-tone lines varies significantly
Railing system	Composite/aluminum rail packages cost more than basic wood rail but need far less upkeep
Site access	Grade, fencing, and how far materials have to be carried affects labor time
Height and stairs	Multi-level decks and stair builds add engineering and framing complexity

The honest range for a composite deck project varies widely based on these factors — we'll walk through them specific to your property during the estimate rather than throw out a number that doesn't mean much without context.

Why It Matters That We Already Work Aldergrove, BC

Cross-border service work has its own logistics — scheduling around crossing times, coordinating material delivery, and understanding that a property a few minutes from the Aldergrove–Lynden crossing gets the exact same weather system as a property on the Lynden side, just with a different mailing address. A crew that's unfamiliar with that reality tends to either overbuild for conditions that don't apply or underbuild for the moss and moisture pressure that does. Because we already do this regularly, there's no learning curve, no guessing on permitting differences, and no surprise scheduling gaps caused by not understanding how close this community actually is to our home base in Lynden.

Signs an Existing Deck Should Be Replaced, Not Repaired

Soft, spongy spots in the decking surface, especially near the house or in shaded corners
Persistent moss or dark staining that comes back within weeks of cleaning
Railing posts that flex or feel loose at the base
Visible gaps or separation where the ledger board meets the house
Rust streaking from fasteners or hardware onto the board surface
A deck older than 12-15 years built with untreated or minimally treated wood in a shaded, damp location

If you're seeing two or more of these, it's usually more cost-effective long-term to rebuild with a moisture-resistant material than to keep patching a wood deck that's fighting this climate every season.

If you're weighing a new composite deck or replacing one that hasn't held up to the weather here, we're happy to come take a look and put together a straightforward, no-pressure estimate — just fill out the form below and we'll get in touch.