Semiahmoo A Fair Look at LP SmartSide
LP SmartSide is an engineered wood siding product, and it's not a bad piece of engineering. It's strand-based wood fiber treated with resins and zinc borate for insect and rot resistance, then coated with a factory finish. For a lot of the country, installed and maintained correctly, it holds up reasonably well. We get asked about it often enough that it's worth explaining, plainly, why we don't put it on homes here in Semiahmoo.
Our answer isn't that the product is junk. It's that we build our business around one material — James Hardie fiber cement — and we think that's the more honest way to run a siding company in this particular corner of Whatcom County.
Why Wood-Based Siding Is a Harder Sell on Semiahmoo Peninsula
Semiahmoo sits right on the water, and that changes the math on any wood-based product. Three things work against engineered wood siding here specifically:
- Salt air. Airborne salt from Semiahmoo Bay and Drayton Harbor settles on exterior surfaces year-round. It doesn't rot wood by itself, but it accelerates finish breakdown, and once a factory coating starts to degrade at the edges or fastener points, the wood substrate underneath is exposed to moisture in a way fiber cement never has to worry about.
- Driving rain off the Strait. Storms coming across the Strait of Georgia and Boundary Bay hit this peninsula sideways more often than they fall straight down. Wood-based siding depends heavily on caulking, flashing, and butt-joint sealing staying perfect for decades. On a fully exposed point of land, that's a lot to ask of any sealant.
- A long moss season. Whatcom County's wet months stretch long, and north-facing walls, roof lines, and anything shaded by fir or cedar trees stay damp for weeks at a time. Moss and algae need exactly that kind of sustained moisture, and once organic growth gets a foothold on a wood-fiber substrate, it holds moisture against the surface even after the weather clears.
None of this means LP SmartSide fails on day one. It means the product's long-term performance leans hard on maintenance discipline — recaulking, repainting field-cut edges, keeping gutters clear, staying ahead of moss — in a climate that gives you less margin for skipped years than a drier region would.
Where Engineered Wood Siding Gets Sensitive
The installation itself is where a lot of the risk actually lives. Every field cut on an engineered wood panel exposes raw wood fiber that has to be sealed with the manufacturer's approved primer before it goes up — skip that step, or miss a spot, and that cut edge becomes the first place moisture gets in. Butt joints, inside corners, and anywhere two panels meet need consistent, high-quality sealant, applied correctly, and re-inspected periodically for the life of the siding. That's a workmanship-dependent system: it performs exactly as well as the caulk gun and the crew's attention to detail on installation day, and stays that way only if someone keeps maintaining it afterward.
We're not willing to sell a homeowner on the peninsula a siding system whose 30-year performance depends that heavily on perfect sealant work being renewed on a schedule, especially on a home taking direct salt spray and driving rain.
Why We Standardized on James Hardie Instead
James Hardie fiber cement is made from sand, cement, and cellulose fiber — there's no wood fiber to feed moss, no organic substrate for salt-driven finish failure to expose. It's non-combustible, which matters given how many Whatcom County homes sit near dry brush and treelines in summer. Hardie's ColorPlus factory finish is baked on and warranted separately from the substrate, so field cuts and touch-ups aren't left exposed the way they can be with wood-based products.
Just as relevant for a coastal peninsula: Hardie makes climate-engineered HZ product lines specifically for wetter, higher-moisture regions, which is the category this stretch of Washington falls into. It's also backed by a transferable warranty, so if you sell the house, the siding's coverage follows it.
Fiber cement isn't zero-maintenance — nothing installed outdoors on Semiahmoo Bay is — but it removes the specific failure points that worry us most about engineered wood in this location: substrate rot from a compromised finish, and moss taking hold in a material that can actually absorb and hold moisture. That's the trade-off that made us stop installing LP SmartSide and put James Hardie on every home we side.
Talk to Us Before You Decide
If you're comparing siding options for a home in Semiahmoo or anywhere else in Whatcom County, we're happy to walk through what we've seen hold up here and why. Reach out for a free, no-pressure estimate — there's no obligation, just an honest conversation about what makes sense for your house and this stretch of coastline.