Glenhaven Siding Two Different Materials, Two Different Bets on the Weather
Homeowners in Glenhaven researching siding almost always run into the same two names: James Hardie fiber cement and LP SmartSide engineered wood. Both are legitimate step-ups from vinyl, and both have a real track record in the Pacific Northwest. But they're built from fundamentally different materials, and that difference matters a lot once you factor in the salt air coming off the water, the driving rain we get for months at a stretch, and the long moss season that follows. This page lays out what each product actually is, where they diverge, and why our crews install only James Hardie.
What LP SmartSide Is
LP SmartSide is an engineered wood product — strand-based substrate (similar in concept to OSB) saturated with zinc borate and resin, then pressed and coated with a SmartGuard finish. It's a genuine improvement over old-school primed wood or hardboard siding from decades past, and LP has put real engineering into resisting moisture and pests. Installed correctly and maintained on schedule, it performs reasonably well in moderate climates.
The catch is that it's still wood at its core. Wood-based products, no matter how well engineered, share wood's basic vulnerability: they swell, wick, and eventually degrade when moisture gets past the factory finish and into a cut edge, a fastener hole, or a caulk joint that's failed. In a climate with occasional rain and long dry spells, that's a manageable risk. In Whatcom County, where driving rain off the Sound can hit siding sideways for days and humidity rarely lets a wall fully dry out, it's a risk we don't think is worth taking on a customer's home.
What James Hardie Is
James Hardie siding is fiber cement — a blend of cement, sand, and cellulose fiber, cured and then finished at the factory with ColorPlus, a baked-on coating rather than a field-applied paint. It's non-combustible, it doesn't swell or rot the way wood-based products can, and Hardie makes climate-specific formulations. For our region, that means the HZ5 product line, engineered specifically for cold, wet, high-moisture climates like ours rather than a one-size-fits-all formula.
Fiber cement isn't magic — it still has to be installed correctly, with proper flashing, clearances, and joint treatment, or any siding product will eventually let water in. But the base material itself doesn't feed mold, doesn't attract woodpeckers or carpenter ants, and holds a factory finish far longer than field-applied paint, which matters when a home is exposed to salt-laden air that accelerates finish breakdown on lesser products.
Side-by-Side
| Factor | LP SmartSide | James Hardie |
|---|---|---|
| Core material | Engineered strand wood | Fiber cement |
| Fire rating | Combustible (treated) | Non-combustible |
| Finish | Factory or field-painted | Factory-baked ColorPlus |
| Moisture behavior | Resists, but wood base can swell if breached | Does not swell or rot |
| Pest resistance | Treated against insects | Not a food source for pests |
| Climate-specific lines | General-purpose | HZ5 engineered for wet/cold regions |
| Repaint interval | Typically sooner | Longer, factory finish holds up |
Why the Glenhaven Climate Tips the Scale
Whatcom County siding takes a specific kind of beating. Salt air off the water accelerates the breakdown of paints and coatings that aren't formulated to resist it. Driving rain, common here for extended stretches, pushes water sideways into joints and seams in a way that dry-climate installations never have to withstand. And the long moss season means anything with an organic component — including treated wood — sits under damp, shaded conditions for months where mold and moisture have time to work. None of these three factors is unique to Glenhaven, but together they add up to an unusually demanding environment for exterior materials.
LP SmartSide can hold up in this climate for a while, especially with diligent maintenance — caulking checked annually, cut edges sealed, gutters kept clear so water doesn't sheet down the wall. But that's ongoing homeowner upkeep, and if it slips for even a season or two, the wood substrate is the part that pays for it. We'd rather not sell a product whose long-term performance here depends on a maintenance schedule being followed perfectly, year after year.
Why We Standardized on Hardie
We made a decision as a company to install James Hardie exclusively — not LP SmartSide, not vinyl, not cedar or primed spruce. It's not that every alternative is a bad product; it's that we'd rather stand fully behind one system that we know performs in this specific climate than split our warranty work and callback risk across several materials with different failure modes. Hardie's HZ5 line was engineered for exactly the conditions Glenhaven throws at a house, the ColorPlus finish holds color and integrity longer against salt air, and the material itself isn't a food source for moisture or pests the way any wood-based product ultimately is.
There's also the warranty question. Hardie's coverage is transferable and well-documented, which matters for resale in a market like ours where buyers increasingly ask what the siding is and how it's warrantied. Fiber cement installed to spec, on a home in this county, is the choice we can back with confidence.
If you're weighing siding options for a home in Glenhaven or elsewhere in Whatcom County, we're happy to walk through your specific situation — sun exposure, wind direction, existing moisture issues — and give you an honest read on what your house needs. Reach out below for a free, no-pressure estimate.