Lynden Siding An Honest Look at LP SmartSide
Homeowners in Lynden ask us about LP SmartSide often, and it's a fair question. It's a widely available engineered wood siding product, it costs less upfront than fiber cement, and plenty of contractors install it. We don't. Not because it's a bad product when installed and maintained correctly, but because our standard is set for Whatcom County's climate, and we'd rather explain our reasoning than just say no.
What LP SmartSide Gets Right
To be fair to the product: LP SmartSide is engineered wood strand siding treated with resins and zinc borate for insect and rot resistance, then coated with a factory finish. It's lighter than fiber cement, easier on installation crews, and holds paint reasonably well when the factory finish is intact. For a lot of parts of the country, it performs fine for years. The issue isn't the factory spec sheet — it's what happens on an actual house near the water, in the rain, for the next 20-30 years.
Why We Don't Put It on Homes Here
Lynden sits inland from the Salish Sea, but Whatcom County still gets the package deal: salt-laden marine air drifting in off Bellingham Bay and the Strait, long stretches of driving rain off the Pacific, and a moss season that can run most of the year on north-facing walls and shaded lots near the Nooksack River corridor. That combination is hard on any wood-based product, and it's the reason we've standardized on fiber cement instead of engineered wood.
Moisture Is the Real Issue
LP SmartSide is still wood at its core — oriented strand board, essentially, dressed up with resin and a factory coating. Wood swells and shrinks with moisture. As long as the factory finish and every cut edge stay sealed, that's manageable. But every field cut, every nail penetration, and every seam is a place where water can get behind that finish and reach the wood substrate underneath. Once moisture gets into an OSB-based product, it doesn't dry out the way solid lumber does — it swells, and swelling at the edges and seams is the most common failure point we see brought up by homeowners looking to replace this kind of siding.
Installation Sensitivity
LP SmartSide's warranty and performance both depend heavily on correct installation — proper flashing, correct fastener placement, factory-primed or sealed cut edges, and adequate clearance from grade and roof lines. That's true of most siding, but the margin for error is smaller with an engineered wood product than with fiber cement. A missed sealed edge or a fastener in the wrong spot might not show a problem for a year or two. In a climate that delivers sustained wet weather for months at a time, small installation mistakes compound faster than they would in a drier region.
Maintenance Burden
Keeping LP SmartSide performing well over decades means staying on top of caulking, touch-up painting at cut edges and seams, and watching for any spot where the finish has worn through. That's a real ongoing commitment for a homeowner, especially on a house with a lot of trim detail or multiple stories. Combine that with the moss growth that's common on shaded and north-facing walls in this area, and you've got a siding product that needs more attention here than it would in a drier climate.
Warranty Structure
Engineered wood siding warranties typically hold up as long as the maintenance schedule is followed and the finish stays intact. That's a reasonable structure, but it puts the burden of proof on the homeowner if a claim ever comes up — did the caulking get redone on schedule, was every cut edge sealed at the time of installation. It's a different kind of warranty conversation than a straightforward, transferable, long-term warranty on a material that doesn't rely on an intact surface coating to resist moisture in the first place.
Why We Install James Hardie Instead
James Hardie fiber cement is our standard for every home we side, and the reasons come directly from the trade-offs above. It's non-combustible and dimensionally stable, so it doesn't swell, warp, or rot the way wood-based products can when moisture finds a way in. Hardie's ColorPlus factory finish is baked on and backed by its own finish warranty, and the HZ5 product line is specifically engineered for harsher, wetter climates like ours. It holds paint and color far longer with far less upkeep, and the installation practices we follow are built around getting flashing, clearances, and fastening right the first time — because that's what makes a 30-plus-year exterior actually last that long in a place that sees this much rain and salt air.
Our Position
We're not going to tell a homeowner that LP SmartSide is junk — it isn't, and it works well for a lot of houses in a lot of climates. But we build our business around one material because we've seen what performs, with the least maintenance and the fewest surprises, on homes exposed to Lynden's rain, moss, and marine air year after year. That's James Hardie, and it's the only siding we put our name behind.
If you're weighing siding options for your home, we're happy to walk through what we see and why — no pressure, no sales pitch, just a straight answer. Request a free estimate below and we'll take a look at your house in person.