Ferndale Siding Built for Life on Lummi Island
Lummi Island sits out in the salt water off the Whatcom County mainland, reachable only by a short ferry crossing from Gooseberry Point near Ferndale. That geography is part of what makes the island a great place to live — and part of what makes it a genuinely harder place to keep a house's exterior in good shape. Homes here take a steady dose of salt-laden marine air, wind-driven rain off the water, and a moss season that runs longer than it does even a few miles inland. Siding installation on Lummi Island isn't the same job as siding installation in a dry subdivision forty miles east, and it shouldn't be treated that way.
This page covers what siding installation actually needs to get right for an island home in this climate, how we approach the job, and why we've standardized on one product system rather than offering a menu of options.
What the Island Climate Actually Does to Siding
Salt Air
Airborne salt from the surrounding water settles on exterior surfaces and accelerates corrosion of exposed metal fasteners, flashing, and trim — and it can degrade some siding finishes faster than the same product would wear on a home a few miles inland. Any material or fastener spec that "works fine in town" deserves a second look before it goes on a waterfront or near-waterfront wall on the island.
Driving Rain
Storms coming off the water don't just fall straight down — wind pushes rain sideways and up under laps, trim, and penetrations. Siding that relies purely on a tight surface seal, rather than a proper drainage plane behind it, is the siding most likely to trap moisture where you can't see it.
A Long Moss Season
Shaded, damp, north-facing walls on the island can stay wet longer into the year than similar walls inland, which extends the window where moss, algae, and mildew can take hold on siding, trim, and fastener heads. Left alone, that growth holds moisture against the surface and speeds up whatever deterioration the material is already prone to.
What Correct Installation Involves Here
The siding product matters, but installation is what actually determines whether a house stays dry for the next twenty-plus years. On Lummi Island specifically, we pay close attention to a few things that get skipped more often than they should:
- A drainage plane behind the siding — a rainscreen gap or weather-resistive barrier system that lets any water that gets past the siding drain and dry out, instead of sitting against the sheathing.
- Correct flashing at every horizontal penetration — windows, doors, deck ledgers, and roof-to-wall transitions are where driving rain finds its way in first.
- Fastener selection suited to a marine environment — the wrong fastener corrodes years before the siding around it fails, leaving rust streaks and eventually a loose panel.
- Proper clearance at grade and hard surfaces — siding installed too close to soil, decking, or concrete stays damp longer and is more exposed to splash-back.
- Manufacturer-spec caulking and joint treatment — done wrong, joints become the first place moss and moisture take hold; done right, they're barely visible and shed water as intended.
Why We Install Only James Hardie Fiber Cement
We don't offer vinyl, LP SmartSide, primed spruce, cedar, or other fiber cement brands as options — not because there's no market for them, but because after years of exterior work in this climate, we standardized on one system we can stand behind on every wall we touch, including the tougher ones out on the island.
James Hardie fiber cement is non-combustible, doesn't rot the way wood-based products can when moisture gets in, and holds up to sustained damp exposure better than materials that depend on a paint film or a resin coating to keep water out. The ColorPlus factory finish is baked on under controlled conditions rather than field-painted, which matters in a climate where you don't always get a long dry stretch to paint or maintain a finish on-site. Hardie's HZ5 product line is engineered specifically for cold, wet climates like ours, and the transferable warranty backs the material for the long haul, not just the first few years.
None of that means other products are junk — it means we made a professional call about what we're willing to warranty our workmanship on, and fiber cement done right is what we believe holds up best against salt air, driving rain, and a long moss season without turning into a maintenance project every couple of years.
How Hardie Compares for an Island Home
| Factor | James Hardie Fiber Cement | Vinyl | Wood / LP SmartSide |
|---|---|---|---|
| Moisture behavior | Doesn't rot; engineered HZ lines for wet climates | Doesn't absorb water, but can trap it behind loose panels | Wood-based core can swell or degrade if moisture penetrates |
| Salt air exposure | Fiber cement core is not corroded by salt; finish holds up well | Can chalk, fade, or become brittle over time in coastal exposure | Coatings and edges are more vulnerable to accelerated wear |
| Fire resistance | Non-combustible | Combustible, can melt or deform near heat | Combustible |
| Finish | Factory-applied ColorPlus, consistent and long-lasting | Color molded through material, can fade | Field-applied paint/primer, needs ongoing maintenance |
| Long-term maintenance | Periodic cleaning; finish holds up for years between recoats | Low maintenance but limited repairability once damaged | Repainting and moisture monitoring on a regular cycle |
Our Installation Process
- On-site assessment. We look at wall orientation relative to wind and water exposure, existing moisture damage, current siding and sheathing condition, and any trouble spots around windows, doors, and roof transitions.
- Scope and product plan. We spec the right Hardie plank, panel, or shingle profile and HZ line for the exposure, along with the drainage and flashing details the specific walls need.
- Tear-off and substrate check. Old siding comes off, and we inspect the sheathing underneath for rot or hidden moisture damage before anything new goes up — this is where problems that have been building for years usually surface.
- Water-resistive barrier and drainage plane. House wrap or equivalent, plus rainscreen furring where the wall assembly calls for it, goes on before any siding.
- Flashing and penetration detailing. Windows, doors, and any wall penetrations get flashed correctly before siding closes around them.
- Siding installation to manufacturer spec. Correct fastener pattern, spacing, and clearances, following James Hardie's published installation instructions — this is what keeps the warranty valid.
- Trim, caulking, and final detail work. Clean joints and correctly sealed transitions are what keep water out and moss from getting a foothold at the seams.
- Walkthrough. We go over the finished work with you before we call the job done.
What Drives Cost on a Lummi Island Job
Every job is different, but these are the factors that most commonly move the price on an island siding project:
| Factor | Why it matters |
|---|---|
| Ferry scheduling and logistics | Material deliveries and crew transport need to work around ferry timing, which affects scheduling more than pricing on most jobs but is worth planning around early |
| Condition of existing sheathing | Hidden rot found during tear-off adds repair work before new siding can go on |
| Wall exposure and complexity | Waterfront-facing walls, multiple stories, and complex rooflines take more time to flash and detail correctly |
| Siding profile and finish selection | Plank width, texture, and color affect material cost |
| Trim and accessory scope | Full trim replacement versus reusing sound existing trim changes both material and labor |
Maintenance in This Climate
Fiber cement is genuinely low-maintenance, but "low-maintenance" doesn't mean "no maintenance" anywhere on the island. A periodic rinse-down keeps salt residue and early moss growth from building up, particularly on shaded and north-facing walls. Keeping gutters clear and vegetation trimmed back from siding helps airflow and drying. Checking caulked joints every year or two and touching up promptly if anything opens up is a small task that prevents a much bigger one later.
Why Hire a Crew That Already Works on the Island
A ferry crossing changes how a project gets planned. Material deliveries, crew scheduling, and even something as simple as making a second trip for a forgotten part all take more coordination than they would on the mainland. A contractor who already builds ferry logistics into their scheduling doesn't lose days to it. Familiarity with how island homes are typically built, oriented, and exposed to wind and water also means fewer surprises once tear-off starts — and a crew that has flashed and detailed walls in this exact kind of exposure before is less likely to leave a gap that shows up as a leak two winters later.
Questions Worth Asking Before You Hire
- Have you installed siding on Lummi Island or similarly exposed coastal properties before?
- How do you handle ferry scheduling for materials and crew?
- What's your plan for the drainage plane and flashing on this specific wall assembly?
- Are you a certified James Hardie installer, and what does that mean for my warranty?
- What happens if you find rot or damage once the old siding comes off?
- What does your written estimate include and exclude?
If your Lummi Island home is due for new siding, or you're seeing early signs of moisture or moss trouble on the walls that face the water, we're happy to take a look and walk you through what correct installation would involve for your specific home. Reach out for a free, no-pressure estimate using the form below.