Ferndale Siding Composite Decking Built for Blaine's Coastal Conditions
Blaine sits right up against Boundary Bay and the Salish Sea, which means homes here deal with a combination of weather that inland Whatcom County properties simply don't face: salt-laden air, wind-driven rain that gets pushed sideways under eaves and railings, and a moss and algae season that can run most of the year in shaded, damp spots. A deck built with the wrong materials or the wrong details will show it within a couple of seasons — cupped boards, corroded fasteners, green film on the walking surface, or soft spots where water has been sitting instead of draining. Composite decking, installed correctly for this environment, holds up to all of that without the constant sanding, staining, and refinishing that wood decking demands out here.
This page is about composite decking specifically for Blaine properties — what the local climate actually does to a deck, what a correct installation looks like in response, and how we handle the job from first look to final walkthrough.
Salt Air, Rain, and Moss: What Blaine Decks Are Up Against
Salt Air and Metal Hardware
Proximity to the bay means airborne salt settles on everything outdoors, including fasteners, brackets, and railing hardware. Standard zinc-coated screws and connectors can start showing rust and pitting well before their inland equivalents would. This doesn't ruin the composite boards themselves, but corroded fasteners loosen their grip, streak the surface with rust stains, and eventually become a structural liability at railing posts and ledger connections.
Driving Rain and Drainage
Storms coming off the water tend to arrive with wind, which pushes rain up under railings, into board gaps, and against the house at the ledger connection. A deck that isn't sloped, gapped, and flashed correctly will trap that water instead of shedding it, and trapped water is what leads to soft framing, mold underneath the deck, and staining nobody can scrub off.
Moss and Algae Season
Whatcom County's damp, mild winters and shoulder seasons are ideal moss and algae growing conditions, especially on decks that sit in shade or under overhangs where the surface rarely fully dries. On wood decking this often means a slick, green, actually dangerous walking surface within a year or two. Composite decking resists this far better, but the surface texture, board spacing, and how much sun and airflow the deck gets still matter for how much maintenance it needs.
What a Correctly Installed Composite Deck Involves
Composite boards are only as good as what's underneath and around them. A lot of decking problems we get called out to fix in this area trace back to shortcuts in the substructure, not the decking material itself.
Substructure and Framing
Composite boards are heavier than wood and often call for tighter joist spacing than a traditional wood deck — this varies by product, and we build to the manufacturer's engineering specs rather than reusing whatever spacing the old wood deck happened to have. Any framing lumber that's exposed to weather gets properly rated and, where it's in ground contact or close to it, treated appropriately for a wet coastal climate.
Fasteners and Hardware
Given the salt exposure in Blaine, we use stainless steel or marine-grade coated fasteners and connectors rather than standard galvanized hardware. It costs a bit more up front, but it's the difference between hardware that's still solid in ten years and hardware that's rust-streaked and loose in three.
Ventilation and Board Spacing
Composite boards need airflow underneath to dry out properly and to let the small gaps between boards do their job of draining surface water. We keep the deck height, joist spacing, and skirting details open enough for air to move rather than sealing the underside in a way that traps moisture — a common mistake that turns a deck into a slow-drying box.
Flashing and Ledger Attachment
Where the deck attaches to the house, proper flashing keeps water from working its way behind siding and into the wall assembly — a detail that matters even more in a climate with as much driving rain as this stretch of coastline gets. This is also the point where a lot of older decks fail first, since it's hidden and easy to skip.
Composite vs. Wood vs. PVC for a Blaine Property
There's no single "best" decking material for every home — it depends on how much maintenance you want to do, how much shade and salt exposure the deck gets, and budget. Here's how the common options stack up for a coastal Whatcom County setting:
| Material | Maintenance | Moisture & Salt Air Behavior | Typical Lifespan |
|---|---|---|---|
| Wood (cedar/pressure-treated) | Annual staining/sealing; regular cleaning to fight moss | Prone to cupping, splintering, and rot without diligent upkeep | 10-15 years before major repair or replacement |
| Composite (capped) | Occasional washing; no staining or sealing | Resists moisture absorption and salt exposure well; hardware is the main vulnerability | 25-30+ years, per most manufacturer warranties |
| PVC/cellular decking | Similar low upkeep to composite | Fully moisture-resistant; lighter weight, different feel underfoot | Comparable to or longer than capped composite |
We install composite most often on Blaine projects because it offers the best balance of low maintenance, appearance, and cost for this climate. PVC is a reasonable option for homes with heavier moisture exposure or where weight is a concern, and we're happy to walk through both if you're deciding between them.
Our Process, Start to Finish
- On-site assessment — We look at sun exposure, drainage, existing framing (if it's a replacement), and how the deck ties into the house.
- Material and layout plan — We go over board options, color, railing style, and fastener systems based on your budget and how the deck will be used.
- Permitting — Depending on size, height, and attachment to the house, the project may need a permit through the local jurisdiction; we handle that paperwork.
- Demo (for replacements) — Old decking and any compromised framing come out, and we inspect what's underneath before building back.
- Substructure build or repair — Framing, joist spacing, and ledger flashing are set to the composite manufacturer's specs, not just matched to what was there before.
- Decking, railing, and trim install — Boards go down with the fastener system specified for the product, followed by railings and any fascia or trim.
- Final walkthrough — We check the deck with you, confirm drainage and finish details, and go over basic care.
Cost Factors for a Blaine Composite Deck
Composite decking costs more up front than pressure-treated wood, but the gap narrows over time once you factor in staining, sealing, and repair costs on a wood deck. Actual pricing depends on the specifics of your project, but the main variables are:
| Factor | Why It Matters |
|---|---|
| Deck size and shape | More square footage and cuts (angles, curves, multiple levels) increase material and labor |
| Substructure condition | New framing or repair of rotted/undersized joists adds cost but is not optional if the existing structure isn't sound |
| Board tier and color | Composite lines range from base capped boards to premium wood-grain finishes at different price points |
| Railing style | Composite or metal railing systems cost more than basic wood but need far less upkeep |
| Fastener and hardware grade | Marine-grade stainless hardware, which we recommend for salt air exposure, costs more than standard coated fasteners |
| Height and access | Elevated decks or difficult site access add labor time |
We give straightforward, itemized estimates so you can see where the money is going rather than a single lump number.
Maintaining a Composite Deck in This Climate
Composite decking is low-maintenance, not no-maintenance, especially with the moss and algae pressure this area sees. A little seasonal attention keeps it looking and performing the way it should:
- Rinse or sweep off leaves, pollen, and debris regularly, especially in shaded areas where moisture lingers
- Wash the deck surface a couple of times a year with a mild soap and soft-bristle brush to prevent moss and algae buildup before it takes hold
- Check railing posts and fastener points periodically for any rust staining or looseness, particularly after storm season
- Keep gutters and downspouts near the deck clear so runoff isn't dumping extra water onto the surface or substructure
- Trim back overhanging vegetation to let more sun and airflow reach shaded sections of the deck
- Avoid pressure-washing at close range or high PSI, which can damage the cap layer on composite boards
Why a Crew That Already Works Blaine Matters
A lot of decking problems we see out here aren't from bad materials — they're from installation details that work fine in a drier inland climate but fail in a coastal one. Fastener choice, ventilation, flashing at the ledger, and even which side of the house gets shaded enough to grow moss are all things you learn by actually working on homes in this specific stretch of Whatcom County, not from a generic install manual. We're based in Ferndale and work throughout the surrounding area, including Blaine, so these aren't unfamiliar conditions to us — they're what we plan for on every deck we build here.
We're also on hand locally if something needs a look after the fact, rather than being a crew that did one job in the area and moved on.
Get a Free, No-Pressure Estimate
If you're weighing a new composite deck or replacing an aging wood one, we're glad to come take a look, talk through material options for your specific site conditions, and give you a straightforward estimate — no pressure, no obligation. Use the form below to get started.