Lynden Siding Composite Decking Built for Custer's Coastal Climate
Custer sits close enough to the water and open farmland that homes here take a steady beating from weather most inland communities never deal with. Salt-tinged air off the Strait, driving rain that comes in sideways for days at a stretch, and a moss season that seems to start earlier every year and end later — all of it works on an outdoor deck year-round, not just in winter. If you're planning a new deck or replacing tired boards in Custer, the material you choose and how it's installed matter more here than in a drier part of the state.
Salt Air and Coastal Exposure
Homes closer to the water pick up airborne salt that settles on every exterior surface, including deck boards, fasteners, and railing hardware. Salt exposure doesn't rot composite decking the way it can degrade untreated metal or accelerate corrosion in cheap fasteners, but it does mean the hardware and connectors used in the build need to be rated for it. This is one of the first things we account for when we spec a job in this area — it's not optional trim, it's part of doing the installation correctly.
Moss, Algae, and a Long Wet Season
Whatcom County's wet season runs long, and shaded or low-airflow areas under trees or against the house hold moisture for weeks at a time. That's exactly the environment moss and algae need to take hold. On a wood deck, moss growth traps moisture against the board and speeds up rot from the inside. Composite decking doesn't feed moss the way wood fiber does, but it isn't moss-proof either — surface growth can still form in the dampest, shadiest corners of a deck if it isn't cleaned occasionally. Board spacing and airflow underneath the deck make a real difference in how much of that problem you actually see.
Why Composite Makes Sense for Custer Homes
We install wood decks too, and there are homeowners for whom wood is still the right call — usually for cost or a specific look. But for a deck that's going to sit through Whatcom County winters year after year with minimal upkeep, composite has real advantages worth weighing honestly against wood.
| Factor | Wood Decking | Composite Decking |
|---|---|---|
| Moisture behavior | Absorbs and releases water; prone to cupping, splitting, checking | Doesn't absorb water into the board fiber; dimensionally stable when wet |
| Moss/algae resistance | Organic surface feeds growth, especially in shaded spots | Non-organic surface resists growth; still needs occasional cleaning in damp corners |
| Maintenance | Annual sanding, staining, or sealing to keep water out | Periodic washing; no staining or sealing required |
| Upfront cost | Lower material cost | Higher material cost |
| Lifespan with normal care | Shorter before boards need replacement or major refinishing | Longer service life with less labor invested over time |
| Fastener/hardware sensitivity | Standard exterior fasteners generally sufficient | Requires composite-rated hidden fastener systems for proper hold and appearance |
The honest trade-off is upfront cost versus ongoing labor. Composite costs more to install; wood costs more in the years afterward, especially in a climate that never really dries out for long. For a lot of Custer homeowners who want to actually use their deck instead of maintaining it, composite pencils out over the life of the deck.
What a Correct Composite Deck Installation Involves
Composite decking is more forgiving than wood in some ways and less forgiving in others. The board itself resists rot, but a poorly built substructure or bad fastening job will still fail — the material doesn't fix bad framing.
Framing and Substructure
The joists, beams, and posts underneath a composite deck still need to be sized and spaced correctly for the board span, and in a wet climate we pay close attention to how the frame handles standing water. Proper slope away from the house, adequate ventilation under the deck, and joist tape or flashing on the framing itself all protect the structure that's actually holding the deck up, even though the visible boards are low-maintenance.
Hidden Fasteners and Board Spacing
Most composite decking today is installed with hidden fastener clip systems rather than face screws, which gives a cleaner look and avoids the screw-hole water entry points that plague older wood decks. Board spacing has to be set correctly — too tight and boards can't expand and contract with temperature changes or shed water properly; too loose and it looks sloppy and catches debris. Getting this dialed in is a matter of following the manufacturer's spec, not guesswork.
Flashing and Ledger Board Connections
Where a deck attaches to the house, the ledger board connection is the single most common source of long-term water damage on any deck, wood or composite. Correct flashing at this joint — installed so water sheds away from the house rather than behind the ledger — is not a step we skip to save time. In a climate with as much annual rainfall as this one, a bad ledger flashing detail shows up as rot in the house framing within a few years, not decades.
Choosing the Right Composite Board for This Climate
Capped vs. Uncapped Composite
Capped composite boards have a protective outer shell wrapped around the composite core, which gives significantly better resistance to moisture absorption, staining, and surface wear than uncapped composite. Given how much rain and standing moisture this area sees, we generally steer homeowners toward capped composite for anything but the most budget-constrained projects — it's the difference between a deck that still looks new in eight years and one that starts to look tired much sooner.
Color and Heat Considerations
Darker composite boards absorb more heat and can get warm underfoot on sunny days, though this region doesn't see the extended high-heat stretches that make this a major issue in other climates. Lighter and mid-tone colors also tend to show less visible dust, pollen, and general grime between cleanings, which matters more here than in a drier climate where dust simply doesn't stick the same way.
Our Process, Start to Finish
- On-site visit to measure the space, check existing framing or foundation conditions, and talk through layout, railing, and stair needs
- Straightforward written estimate — materials, labor, and timeline, no vague allowances
- Structural check and any needed repair or reinforcement of ledger, posts, footings, or joists before decking goes down
- Proper flashing and moisture management installed at every point the deck contacts the house
- Composite board installation with hidden fasteners, correct spacing, and attention to drainage and airflow underneath
- Railing, stair, and code-required safety details completed to current standards
- Final walkthrough with the homeowner before we consider the job done
Railings, Stairs, and Code Considerations
Deck railings and stairs are subject to building code requirements around height, baluster spacing, and load, and Whatcom County permitting applies to most new deck construction and many replacement projects depending on scope. We handle the permitting conversation as part of the estimate rather than leaving it as a surprise later. Composite decking pairs with a range of railing systems — composite, aluminum, cable, or a mix — and the right choice usually comes down to sightlines, maintenance preference, and budget rather than the decking material itself.
Maintenance: What Custer Homeowners Actually Need to Do
Composite decking is genuinely low-maintenance, but "low" isn't "zero." A seasonal rinse with a hose and soft brush, especially in shaded corners or under furniture where debris collects, keeps surface grime and any early moss or algae from taking hold. Keeping planters, pots, and furniture from sitting in one spot for months at a time helps airflow reach the whole deck surface. Clearing leaves and debris out of the gaps between boards before the wet season sets in prevents the kind of trapped moisture that causes problems even on a material that doesn't rot.
Why a Local Crew That Already Works Custer Matters
A deck built for a dry climate and a deck built for this one aren't the same project, even if the material list looks identical on paper. Knowing how much rain this area actually gets in a wet month, how far salt air travels inland from the water, and which corners of a yard hold moisture longest changes real decisions — slope, flashing detail, fastener choice, board spacing. A crew that already works in and around Lynden and Custer has made those calls on other decks nearby and isn't learning the local conditions on your project.
If you're weighing a new composite deck or replacing an aging wood one, we're happy to come take a look, walk the site, and give you a straightforward, no-pressure estimate — just fill out the form below to get started.