Lynden Exterior Composite Decking Built for Custer's Coastal Conditions
Custer sits close enough to the water that homes here deal with a different mix of weather than decks further inland in Whatcom County. Salt-laden air off the Strait, long stretches of driving rain, and a moss season that seems to start earlier and last longer every year all put real stress on outdoor living spaces. A deck built without those specifics in mind will show it within a few seasons — chalky fastener heads, green streaking on the shaded side, boards that cup or gap unevenly. Composite decking, installed correctly, handles this environment better than wood, but "installed correctly" is doing a lot of work in that sentence. This page covers what that actually means for a home in Custer.
Why Custer's Climate Changes the Job
It's tempting to treat decking as a one-size-fits-all product, but the environment a deck sits in changes how it should be built, not just what it's built from.
Salt Air and Metal Fasteners
Proximity to the water means airborne salt settles on every exterior surface, including the hardware holding your deck together. Standard fasteners corrode faster here than they would twenty miles inland. We spec stainless steel or coated fasteners rated for coastal exposure on every Custer project, along with hidden fastener systems where the board profile allows it — fewer exposed metal points means fewer places for corrosion to start and less staining on the board surface over time.
Driving Rain and Water Management
Rain that comes in at an angle, which is common here, gets up under railings, against ledger boards, and into any gap in the flashing. A composite deck can be moisture-resistant on the surface and still rot the structure underneath if the framing and flashing weren't detailed for wind-driven rain. We pay particular attention to ledger board flashing where the deck meets the house, since that's the single most common point of hidden water damage on decks in this area, regardless of what decking material sits on top.
Moss and Shade
Custer's tree cover and marine-layer humidity create long stretches where deck surfaces simply don't dry out between rains. Moss and algae take hold fastest on north-facing sections, under overhangs, and anywhere leaf litter collects. Composite boards with a cap layer resist staining far better than uncapped composite or wood, but no surface is moss-proof if drainage and airflow underneath the deck are poor. Board spacing and joist height off grade matter as much as the product itself.
What a Correct Composite Deck Install Involves
A composite deck is only as good as the structure underneath it. The visible boards get most of the attention, but the framing, fastening, and drainage decisions are what determine whether the deck still looks and performs well in ten years.
- Pressure-treated or coastal-rated framing sized and spaced for the specific composite product's span ratings
- Proper ledger board flashing and house-side waterproofing, sealed before the first board goes down
- Joist tape or a comparable protective barrier on top of framing to slow moisture wicking into the wood structure
- Corrosion-resistant or hidden fastening system appropriate for salt air exposure
- Board gapping calculated for the specific composite's expansion behavior in temperature swings
- Adequate clearance and ventilation underneath the deck to let air move and moisture escape
- Picture-framed or finished edges with manufacturer-approved trim to seal cut ends from moisture intrusion
Skipping any one of these doesn't necessarily show up on install day — it shows up two or three winters later, which is exactly why homeowners sometimes get surprised by a "low-maintenance" product that isn't performing the way it was sold.
Comparing Decking Options for a Custer Home
Homeowners often ask us to weigh composite against the alternatives directly. Here's how they generally compare under the conditions Custer actually sees:
| Factor | Composite | Pressure-Treated Wood | Cedar |
|---|---|---|---|
| Moisture/rot resistance | High — capped boards shed water, don't absorb | Moderate — treatment slows rot, doesn't stop it | Moderate — natural oils help but fade with weathering |
| Moss/algae resistance | Good, especially capped products; still needs airflow | Low — porous surface holds moisture | Low to moderate |
| Salt air / fastener corrosion risk | Low if hidden or coated fasteners used | Moderate — standard hardware corrodes faster | Moderate |
| Annual maintenance | Occasional wash-down | Sealing/staining every 1-2 years | Sealing/staining every 1-2 years |
| Upfront cost | Higher material cost | Lowest material cost | Mid to high |
| Long-term cost | Lower over 15-20 years | Higher due to recurring maintenance and replacement | Higher due to recurring maintenance |
Composite isn't automatically the right call for every budget or every project — a covered, low-exposure deck may do fine in wood for years. But for an uncovered deck in Custer's salt air and rain pattern, composite's upfront cost tends to pay for itself in avoided maintenance and replacement.
Why We Don't Cut Corners on Fastening and Flashing
Some crews treat decking as a surface-level swap: pull up old boards, screw down new composite, done. That approach can look fine at handoff and still fail early, because composite decking doesn't forgive bad substructure work the way wood sometimes does — a rotted joist under wood decking is at least visible when you walk the deck; under composite, it can hide longer because the surface doesn't show the same warning signs. Our standard is to treat the frame, flashing, and fastening as the actual job, with the decking itself as the finish layer on top of work that's already done right. That's a more thorough process than a straight board swap, and we're upfront about that with every Custer estimate.
Our Process for a Custer Composite Deck
1. On-Site Assessment
We walk the existing structure (if there is one) or the build site, checking grade, drainage, sun/shade exposure, and proximity to salt air influence. This tells us what framing, flashing, and fastener spec the job actually needs.
2. Product Selection
We walk through composite options with you based on your budget, the deck's exposure, and how much upkeep you want to do. Capped composite is our default recommendation for uncovered, salt-exposed decks in this area.
3. Structural and Flashing Work
Framing, ledger flashing, and moisture barriers get addressed before a single composite board is installed. This is the stage that determines the deck's actual lifespan.
4. Installation
Boards go down with the fastening system and gapping spec matched to the product and the site's climate exposure.
5. Finish and Walkthrough
Edges, trim, and railings get finished, and we walk the completed deck with you so you know what maintenance (if any) it actually needs.
Maintenance: What Custer Homeowners Actually Need to Do
Composite decking's biggest selling point is lower maintenance, not zero maintenance. In Custer's climate, a realistic maintenance routine looks like:
- Rinse or sweep debris off the deck regularly, especially in fall when leaf litter accumulates faster in shaded areas
- Wash the surface once or twice a year with a mild cleaner to prevent moss and algae from taking hold, particularly on north-facing or covered sections
- Check underneath the deck periodically for standing water, blocked drainage, or vegetation growth that traps moisture against the structure
- Inspect fasteners and hardware annually for early signs of corrosion, especially on decks closer to the water
None of this is heavy work, but skipping it entirely — treating composite as maintenance-free — is how a good deck starts looking tired well before it should.
Why Local Experience with Custer Homes Matters
A contractor who mostly works inland jobs may not think twice about standard fastener hardware or skip the extra flashing detail at the ledger board, because those shortcuts don't fail as fast in a drier, less exposed setting. In Custer, they fail faster, and the homeowner is the one who finds out. Working regularly in this part of Whatcom County means we spec hardware, flashing, and drainage details as the default, not as an upgrade — because we've seen what the local climate does to decks that skip them. It's the difference between a deck that ages predictably for two decades and one that needs early repairs the homeowner didn't budget for.
Get a Straight Answer on Your Deck
Every Custer property has its own mix of sun exposure, shade, grade, and distance from the water, and that mix should inform the deck spec, not just the board color you pick. If you're planning a new composite deck or replacing an aging one, we're happy to walk the site, look at what the current structure is doing, and give you a straightforward estimate with no pressure to sign anything on the spot. Use the form below to request a free estimate.