Orcas Island Siding Two Different Materials, One Island Climate
If you're re-siding a home on Orcas Island, you've probably run across both James Hardie fiber cement and LP SmartSide engineered wood siding. Both are legitimate, widely used products with real manufacturer backing. They are not the same material, though, and they don't respond to San Juan County weather the same way. This page walks through how each one is built, how each one handles our specific conditions, and why our crews install James Hardie exclusively.
What Each Product Actually Is
James Hardie siding is fiber cement — a mix of Portland cement, sand, and cellulose fibers pressed into boards and panels. It's inorganic at its core. It doesn't have wood grain to swell, and it isn't a food source for the organisms that go after cellulose in a damp climate. Hardie's ColorPlus finish is baked on at the factory in a controlled environment, rather than field-applied paint.
LP SmartSide is an engineered wood product — strands of wood fused with resins under heat and pressure, then treated with a zinc borate formulation to resist fungal decay and insects. It's a genuine step up from old-style hardboard or untreated wood siding, and LP backs it with a real warranty. It's still, fundamentally, a wood-based product with a factory-primed or factory-finished surface.
Where the Difference Shows Up: Moisture
Orcas Island sees a long, wet shoulder season, salt-laden air off the water, and the kind of driving rain that finds every gap in a building envelope. That combination is exactly where the two materials diverge:
- Fiber cement doesn't absorb water into its structure the way wood does. Cut edges, fastener penetrations, and butt joints still need to be treated correctly — that part is non-negotiable on any product — but the material itself isn't feeding decay if a seal gets compromised over time.
- Engineered wood is treated to resist moisture and decay, and that treatment does real work. But it's still wood at its core, which means cut edges, fastener heads, and any spot where the factory finish is breached become the places where prolonged moisture exposure matters most. In a climate with our rain totals and humidity, that shifts more of the long-term performance onto how well the caulking, flashing, and touch-up paint are maintained year after year.
Salt Air and the Long Moss Season
Being surrounded by the Salish Sea means Orcas homes deal with airborne salt settling on every exterior surface, along with the shaded, damp conditions that let moss colonize roofs, decks, and siding for a good chunk of the year. Moss and algae need organic material and moisture to establish themselves. An inorganic surface like fiber cement gives them less to hold onto, and Hardie's factory finish resists the surface breakdown that gives spores something to grip. It still needs the occasional wash, but it's not fighting the same uphill battle a wood-based product is in a shaded, north-facing wall that barely dries out between October and May.
Fire Consideration
San Juan County has its own wildfire risk profile, and it's worth a mention: James Hardie fiber cement is non-combustible. LP SmartSide, being wood-based, is not. For most island homes this isn't the deciding factor, but for properties near dry brush, tree lines, or with defensible-space concerns, it's a real difference worth knowing about.
Warranty and Long-Term Cost
Both manufacturers stand behind their products, but the structure of the coverage differs. James Hardie's ColorPlus finish carries a long, transferable finish warranty separate from the substrate warranty, which matters if you sell the home — a real consideration on an island where turnover often comes with a change in how carefully a place has been maintained. LP SmartSide's warranty is also solid, but as with any wood-based product, the fine print around moisture exposure and maintenance requirements tends to carry more weight over a 20- or 30-year horizon.
| Factor | James Hardie Fiber Cement | LP SmartSide Engineered Wood |
|---|---|---|
| Core material | Cement, sand, cellulose fiber | Wood strand composite |
| Moisture behavior | Does not swell or rot; edges still need proper detailing | Treated against decay; cut edges and fasteners need ongoing vigilance |
| Combustibility | Non-combustible | Combustible |
| Finish | Factory-baked ColorPlus | Factory-primed or pre-finished |
| Best fit here | Well suited to salt air, rain, and moss exposure | Performs best with disciplined caulk/paint maintenance in wet climates |
Why We Standardized on James Hardie
We made a decision, as a company, to install James Hardie exclusively rather than offer both products side by side. Part of that is climate-driven — Hardie makes an HZ5 formulation specifically engineered for harsher, wetter climate zones, and Orcas Island's exposure to salt spray and sustained rain is exactly the kind of environment it's built for. Part of it is simpler than that: we'd rather stand behind one system we know inside and out, install to spec every time, and back it with a warranty structure we trust, than split our crews' expertise across products with different installation requirements and different long-term maintenance expectations.
None of this is a knock on LP SmartSide as a manufactured product — it has a legitimate place in the market. It's just not what we choose to put on island homes, given what this climate does to a house over the decades it's expected to last.
If you're weighing siding options for a home on Orcas Island, we're happy to walk your property, talk through what we're seeing, and give you a straight, no-pressure estimate for James Hardie siding — no obligation either way.