How long does it typically take to build a custom deck?

A straightforward deck can go from framing to finished decking in about a week of on-site work, though weather windows in Whatcom County's wet months can stretch that out. Larger decks with stairs, custom railing, or extra framing take longer. Permitting time runs separately from build time and varies by scope.

What should I ask a deck builder before hiring them in Blaine or Semiahmoo?

Ask what fastener and hardware grade they use, since standard hardware corrodes faster this close to salt water. Ask how they detail the ledger flashing, since that connection is the most common failure point in this climate. Also ask whether they pull the permit themselves and whether they've built decks elsewhere in the area.

Is composite decking actually better than wood for a property near the water?

It depends on how much upkeep you want to take on. Composite doesn't absorb water or rot the way wood can and skips the sealing/staining cycle, but it costs more upfront and can still grow surface algae in shaded, wet spots. Wood costs less initially but needs a consistent sealing schedule to hold up to salt air and rain.

Why does fastener and hardware choice matter so much for a deck here?

Standard interior-grade screws and hardware can start corroding within a season or two in salt-laden coastal air. Corrosion weakens the connection long before it's visually obvious, which is a safety concern at stair and railing connections especially. We use stainless steel or hardware rated for coastal and ground-contact exposure for that reason.

Does building a deck in Blaine require a permit through Whatcom County?

Most decks above a certain size or height off grade need a permit, whether that's through Whatcom County or the City of Blaine depending on where the property sits. Requirements can also depend on proximity to shoreline areas around Semiahmoo Bay. We handle the permit process as part of the build rather than leaving it to the homeowner.

Blaine Custom Decks Built for Semiahmoo's Coastal Climate

Building Decks in Blaine's Coastal Climate

Blaine sits right on Semiahmoo Bay, and that waterfront setting is exactly what makes a custom deck here different from one built further inland. Properties near the bay and Drayton Harbor deal with salt-laden air moving in off the water, long stretches of driving rain through the fall and winter, and a moss season that can run from October well into spring. A deck built without those three factors in mind will show problems years before it should — corroded hardware, soft spots at the ledger, black streaks and slick moss on the walking surface. A deck built correctly for this climate will outlast all of that.

This page covers what we build into every custom deck we put up in the Blaine area, why it matters for a Whatcom County coastal property specifically, and what to expect if you're planning one.

What Salt Air, Rain, and Moss Actually Do to a Deck

Salt Air and Corrosion

Wind off Semiahmoo Bay carries fine salt spray further inland than most homeowners expect, especially on exposed or elevated lots. Salt air accelerates corrosion in anything ferrous — screws, joist hangers, bolts, post bases. Standard hardware can start rusting and staining decking within a season or two this close to the water. Once a fastener starts to corrode, it loses holding strength long before it looks obviously bad.

Driving Rain

Whatcom County's rain doesn't just fall straight down — coastal wind pushes it sideways into ledger connections, stair stringers, and any spot where two pieces of framing meet. That means flashing details that would be optional in a drier climate are not optional here. Water that gets behind a ledger board or into an unsealed end cut sits there, and untreated framing lumber in contact with standing moisture starts breaking down from the inside before any surface rot is visible.

Moss and Algae

Shaded decks, north-facing decks, and anything under tree cover in this area grow moss and algae on a predictable schedule if the surface can't dry out between rain events. Beyond looking bad, wet moss is genuinely slick — it's one of the more common reasons for falls on older decks in this part of Washington. Board spacing, airflow underneath, and surface texture all affect how fast that buildup happens.

Choosing Decking Material for a Semiahmoo-Area Property

There's no single "best" decking material — the right call depends on how exposed the site is, how much maintenance the owner wants to do, and budget. Here's how the common options actually perform in this specific climate:

Material	How it handles salt air & rain	Moss/algae resistance	Maintenance
Cedar	Naturally rot-resistant if finished and maintained; end grain and fasteners are the weak points	Needs regular cleaning and periodic sealing to resist growth	Sealing/staining every 1-2 years
Pressure-treated fir/hem-fir	Treatment protects against rot but requires consistent sealing to shed water	Prone to moss without upkeep	Sealing every 1-2 years, board checks over time
Composite (capped)	Doesn't absorb water or rot; hardware still needs to be corrosion-rated	Can still grow surface algae in shaded, wet spots — needs occasional washing	Occasional cleaning, no sealing/staining
Tropical hardwood (e.g., ipe)	Very dense and naturally weather-resistant; expensive and heavier on framing	Better natural resistance but still needs cleaning in shade	Periodic oiling to maintain color, otherwise low

For fully exposed, sun-hit decks near the water, cedar and pressure-treated lumber both do fine as long as the finish schedule is kept up. For shaded lots or homeowners who don't want a recurring sealing job, capped composite tends to be the more honest long-term choice — not because wood is a bad product, but because the maintenance burden on wood in this climate is real and ongoing.

What a Correctly Built Deck Includes Here

Regardless of decking material, the parts of a deck that actually determine whether it lasts are underneath the surface. In a climate like this, we treat the following as non-negotiable:

Ledger flashing that sheds water away from the house band board, not just a bead of caulk behind the ledger
Stainless steel or heavy hot-dip galvanized fasteners and hardware rated for coastal/ground-contact exposure — not standard interior-grade coated screws
Joist tape or an equivalent cap on top of every joist so fasteners don't sit in a moisture trap
Proper board spacing for drainage and airflow, adjusted slightly tighter or wider depending on decking material and sun exposure
Footings set to local frost and drainage requirements, with positive drainage away from posts
Stair stringers and any framing near grade kept clear of soil contact and standing water

Skipping any one of these doesn't usually show up in year one. It shows up in year four or five, as soft framing, rust streaks bleeding through decking, or a ledger connection that's failed quietly behind the siding.

Our Process for a Blaine Custom Deck

Every property on or near Semiahmoo Bay sits a little differently — some are fully exposed to wind and salt spray, some are tucked back and dealing more with shade and moss. We start by looking at the actual site rather than applying one standard spec to every job:

Site walk-through: we look at sun exposure, wind exposure, drainage around the foundation, and how the existing siding and framing are holding up where the deck will attach.
Design and material conversation: we go over decking and framing options honestly, including what each one will actually cost you in upkeep over the next 10-15 years, not just up front.
Permit and code check: decks over a certain size or height typically require a permit through Whatcom County or the City of Blaine depending on the property — we handle that step rather than leaving it to the homeowner.
Build: framing, flashing, and fastener details go in first and get inspected before decking goes down, since those are the parts that can't be checked once the surface is closed up.
Final walkthrough: we go over the finished deck with you, including what maintenance schedule makes sense for the material you chose.

Maintenance to Expect Living Near Semiahmoo Bay

No deck in this climate is truly maintenance-free, even composite. What changes by material is how much and how often. A realistic annual routine for a Blaine-area deck looks like:

Rinse or sweep off moss and organic debris before it has a chance to establish, especially in shaded corners and against the house
Check fastener heads and hardware once a year for early rust staining, particularly on railings and stair connections
Keep gutters and downspouts near the deck clear so runoff isn't dumping extra water onto or under the deck surface
Reseal or restain wood decking on the schedule the product calls for — stretching this out is the single most common reason wood decks fail early here
Trim back vegetation that's shading the deck surface if moss keeps coming back in the same spots

Why a Crew That Already Works Blaine Matters

A deck built by someone who hasn't worked this stretch of Whatcom County coastline will often use hardware and details that are fine for a drier inland climate but undersized for salt air and driving rain here. As Semiahmoo Siding Company, we already work on homes throughout Blaine and the surrounding Semiahmoo area — we're not learning the local exposure conditions on your project. That matters for material selection, for knowing which lots need extra flashing attention, and for understanding how local permitting works before we ever pull a permit.

It also matters after the build. A local crew is the one you can actually call in a few years if a board needs replacing or a railing connection needs a look, instead of chasing down a company that only worked the area for one project.

What Moves the Price on a Custom Deck

Every deck is priced on its own size, material, height off grade, and site conditions, so we won't put a number on your project without seeing it. In general terms, the factors that move the price the most are:

Factor	Why it changes cost
Decking material	Composite and hardwood cost more upfront than pressure-treated or cedar, but shift maintenance cost and effort down the line
Height off grade & stairs	More framing, more footings, and more stair stringers and railing all add labor and material
Site access & slope	Waterfront and sloped lots common around Semiahmoo Bay can require more site prep and footing work
Railing style	Cable, glass, and custom rail systems cost more than standard baluster railing
Attachment to house	Ledger work that requires opening up siding or flashing repair adds time versus a simple freestanding deck

We'd rather walk your property and give you a real number than guess at one here.

If you're planning a new deck or replacing an older one in Blaine or anywhere around Semiahmoo, we're happy to take a look and put together a free, no-pressure estimate. There's a form below — send us a bit about your property and we'll get back to you.