Bellingham Two Products, One Big Difference in What They're Made Of
Homeowners in Bellingham and across Whatcom County usually come to us comparing two "upgrade" sidings: James Hardie fiber cement and LP SmartSide engineered wood. Both are marketed as durable alternatives to vinyl, and both look good on a spec sheet. But they're fundamentally different materials, and that difference matters a lot once you factor in our salt air, driving rain, and long moss season. We install only James Hardie. Here's the honest reasoning behind that, including what SmartSide gets right.
What LP SmartSide Actually Is
LP SmartSide is an engineered wood product — strands of wood fiber bonded with resin under heat and pressure, similar in concept to OSB sheathing, then treated with a zinc borate additive to resist fungal decay and insects. It's primed at the factory, comes in panel and lap-siding formats, and it installs faster and lighter than fiber cement because it's a wood-based product through and through.
Credit where it's due: SmartSide is a real step up from untreated cedar or spruce siding, it takes fasteners easily, and it's noticeably cheaper than fiber cement on material cost. For a builder working on a tight budget in a dry climate, it's a defensible choice.
Why We Don't Put It on Homes Here
Whatcom County isn't a dry climate. Bellingham sits on Puget Sound, which means salt-laden air along the waterfront and low-lying neighborhoods, plus a wet season that runs long and a fall/winter moss season that coats north-facing walls, fence lines, and anything shaded for weeks at a time. Wood — even engineered, resin-bonded wood — is still wood at its core, and wood's weak point is moisture intrusion at cut edges, fastener penetrations, and butt joints. Field cuts on SmartSide have to be re-sealed with primer and caulk exactly per LP's instructions, every time, or that engineered core is exposed to exactly the kind of driving rain we get off the Sound.
Caulk and paint are maintenance items. They fail eventually — UV breakdown, seasonal movement, a crew that didn't seal a cut edge quite right five years before we ever see the house. When that seal fails on a wood-based product in a climate that stays damp for months, moisture gets in before anyone notices, because the damage starts on the inside of the panel, not the outside where you'd see it.
Fiber cement doesn't have that vulnerability. James Hardie siding is Portland cement, sand, and cellulose fiber — there's no wood core to swell, rot, or feed fungal growth, and it's non-combustible. Moss and algae still land on any exterior surface in this climate, but they're growing on the surface finish, not feeding on the substrate underneath it.
Side-by-Side, Honestly
| Factor | LP SmartSide (Engineered Wood) | James Hardie (Fiber Cement) |
|---|---|---|
| Core material | Wood strand + resin, zinc borate treated | Cement, sand, cellulose fiber |
| Combustibility | Combustible (wood-based) | Non-combustible |
| Moisture behavior | Resists decay when sealed properly; vulnerable if seals fail | Does not swell, rot, or support fungal growth |
| Finish | Factory primed, field-painted | ColorPlus factory-baked finish available (or field-painted) |
| Cut-edge maintenance | Must be primed/sealed on every field cut | Recommended but far less consequential if missed |
| Material cost | Lower | Higher |
Moss Season Is a Real Design Factor Here
If you've owned a home in Whatcom County for more than a wet winter, you know moss doesn't wait for an invitation. Shaded elevations, gutters that overflow, and north walls near mature trees all collect enough moisture to grow something green whether your siding is wood, fiber cement, or vinyl. The difference is what happens underneath that moss over years. On a fiber cement wall, a periodic wash and a resealed caulk joint keeps the wall performing exactly as it did on day one. On a wood-based wall, sustained surface moisture next to any compromised seam is a slower, quieter path to core damage — the kind you don't see until a repaint reveals it.
Factory Finish vs. Field Paint
ColorPlus, Hardie's factory-baked finish, is baked on before the boards ever reach the jobsite and is backed by its own finish warranty separate from the substrate warranty. SmartSide ships primed, which means the actual color coat is applied on site or shortly after — a step that depends on weather conditions and workmanship at time of install, and one that starts a maintenance repaint clock from day one rather than years down the road.
Why We Standardized on One System
We made the decision to install James Hardie exclusively rather than carry both product lines. Crews that install one system all day, every day, know its flashing details, its fastener schedule, and its caulking points cold — that consistency is worth more to the long-term performance of your siding than having a cheaper option to upsell against. It also means every warranty conversation, every color match, and every repair down the line runs through one system we know inside and out, on a coastline that doesn't forgive shortcuts.
If you're weighing siding options for a home anywhere in Bellingham or Whatcom County, we're glad to walk your specific house — sun exposure, moss-prone elevations, wind-driven rain sides — and give you a straight answer, not a sales pitch. Reach out for a free, no-pressure estimate and we'll show you exactly what a Hardie installation would look like on your home.