Blaine What LP SmartSide Actually Is
LP SmartSide is an engineered wood siding product made from strand-based wood fiber, resin, and a zinc borate treatment (LP calls it SmartGuard), pressed into panels or lap boards and finished with a factory primer or pre-finished coating. It's a legitimate building product with a real place in the market — it's lighter than fiber cement, easier on saw blades, and priced attractively for builders working to a tight budget. We're not writing this page to tell you it's junk. We're writing it because we get asked "why don't you install LP SmartSide?" often enough, from Blaine to Birch Bay to Custer, that it deserves an honest answer instead of a shrug.
The short version: we install James Hardie fiber cement siding exclusively, and we made that call based on how these two product categories actually perform in Whatcom County's specific climate over a 20-30 year window — not just how they look on install day.
What LP SmartSide Gets Right
Credit where it's due. LP SmartSide is easier to cut and handle on a job site than fiber cement, which means faster installs and less silica dust exposure for crews. It holds paint well when properly sealed, comes in lap, panel, and trim profiles that mimic traditional wood siding closely, and its engineered-wood core resists the cupping and splitting you'd get from solid-sawn cedar. For interior applications or drier climates, a lot of installers have good long-term experience with it.
Why We Don't Install It
It's a wood product, and wood needs a dry environment to last
Strip away the marketing and SmartSide is still wood fiber held together with resin. The zinc borate treatment resists fungal decay and insects, but it doesn't make the product waterproof — it makes it decay-resistant as long as moisture is properly managed. Every cut edge, every fastener penetration, and every seam is a place where that resin-bound wood core is exposed unless it's field-sealed correctly, every time, by every installer on the crew.
Edge swelling is the single most common callback
The most reported issue with engineered wood siding across the Pacific Northwest is edge and butt-joint swelling — the ends of boards absorbing water at cut lines, seams, and around penetrations (hose bibs, light fixtures, vents) and puffing up. Once that happens, paint cracks at the swollen edge, water gets behind the finish, and the repair is a board replacement, not a touch-up. This isn't a defect unique to one bad batch; it's the predictable failure mode of a moisture-sensitive substrate installed in a wet climate.
It depends heavily on installer discipline
LP's own installation instructions are detailed and specific for a reason: field-cut edges must be primed before installation, joints need to be caulked with the right sealant, flashing and clearances have to be exact, and touch-up paint has to happen promptly on any exposed cut. When all of that is followed to the letter, the product performs closer to its rated lifespan. When a crew is moving fast on a production schedule, steps get skipped, and the homeowner doesn't find out until the siding is failing five or ten years later. We didn't want to be in the position of promising a homeowner a product that only works if every single detail is executed perfectly for the life of the house.
The warranty structure reflects the risk
LP's warranty is prorated and has real exclusions around improper installation and inadequate maintenance — which is standard for the category, but it means the manufacturer is also acknowledging that field execution and ongoing upkeep matter enormously to how long the product lasts. That's a lot of the performance risk sitting on the homeowner and the installer rather than on the product itself.
Why Blaine's Climate Makes This Worse, Not Better
Whatcom County isn't the wettest corner of Western Washington, but Blaine sits right on the Strait of Georgia, and that location stacks three separate stresses on any wood-based siding.
Salt air
Homes near Semiahmoo Bay, Drayton Harbor, and the Blaine waterfront take on airborne salt that accelerates corrosion of fasteners and metal flashing and keeps painted surfaces damp longer than they would be further inland. Any coating failure or exposed fastener head becomes a faster path for moisture intrusion in a salt-air environment than it would be in, say, Sumas or Everson.
Driving rain off the Strait
Storms coming across the Strait of Georgia and Boundary Bay hit Blaine and Birch Bay with wind-driven rain that pushes water sideways into siding, not just straight down. That's exactly the condition that finds unsealed cut edges and open joints — the weak points of an engineered wood system.
A long moss season
Whatcom County's mild, wet fall-through-spring stretch is ideal moss and algae weather. Moss holds moisture against a siding surface for extended periods, which is a minor cosmetic issue on fiber cement and a real durability issue on a moisture-sensitive wood substrate, especially on north-facing walls and shaded elevations that never fully dry out between rain events.
None of these three factors are exotic — they're just the normal weather pattern for anyone living between Birch Bay and the Canadian border. But they add up to a climate that's genuinely tougher on wood-based siding than the national average conditions those products are rated against.
LP SmartSide vs. James Hardie Fiber Cement
| Factor | LP SmartSide (Engineered Wood) | James Hardie (Fiber Cement) |
|---|---|---|
| Core material | Wood strand + resin, zinc borate treated | Cement, sand, cellulose fiber — non-combustible |
| Moisture behavior | Decay-resistant but swells at unsealed edges/cuts | Dimensionally stable, does not swell or rot |
| Salt air / coastal exposure | Requires diligent sealing and touch-up over time | Factory ColorPlus finish holds up well to coastal air |
| Moss/algae resistance | Sustained moisture is a durability concern | Sustained moisture is mainly a cleaning issue |
| Fire rating | Combustible (treated, not fireproof) | Non-combustible |
| Typical warranty | Prorated, with maintenance requirements | Non-prorated 30-year limited (ColorPlus finish separate coverage) |
| Field sensitivity | High — cut edges must be primed/sealed immediately | Lower — cut edges don't absorb water the same way |
The Maintenance Burden Homeowners Don't Always Hear About Upfront
Any siding needs some maintenance. The difference with engineered wood is that the maintenance isn't optional cosmetic upkeep — it's structural protection. Here's what keeping LP SmartSide performing to spec actually requires over time:
- Inspecting and re-caulking joints, seams, and penetrations on a regular schedule, not just when something looks obviously wrong
- Repainting or recoating before the factory or field finish starts to fail, not after — once bare substrate is exposed, the clock starts on moisture absorption
- Prompt touch-up of any scuff, impact mark, or scratch that exposes the wood core, especially near grade or under eaves
- Keeping gutters, downspouts, and grading directing water away from the wall plane, since splashback at the base course is a common failure point
- Periodic washing to keep moss and algae from establishing on shaded or north-facing elevations
- Watching butt joints and corner boards closely in year 5-10, since that's typically when swelling first shows up if sealing wasn't perfect
That's a real ongoing commitment, and it's one a lot of homeowners aren't told about clearly at the point of sale. We'd rather a Blaine homeowner know that going in — whether they hire us or someone else.
Why We Standardized on James Hardie Instead
James Hardie fiber cement is made from cement, sand, and cellulose fiber rather than wood, so it doesn't swell, rot, or feed insects the way an organic substrate can. It's non-combustible, which matters to a lot of homeowners and to insurers. Hardie's HZ5 product line is engineered specifically for climates like ours — freeze-thaw cycling, sustained moisture, and coastal exposure — rather than a one-size-fits-all national spec. The ColorPlus factory finish is baked on under controlled conditions rather than field-applied, which removes a lot of the installer-dependent risk we described above, and it carries its own finish warranty separate from the substrate warranty.
None of that means Hardie is maintenance-free — it still needs proper caulking at joints, correct clearance from grade and roof lines, and normal exterior upkeep like any siding. The difference is that when Hardie sees moisture it wasn't supposed to see, the consequence is usually a paint or caulk issue, not a swelling, rotting substrate. In a Blaine microclimate with salt air, sideways rain, and months of moss weather, that distinction matters more than it would somewhere drier.
Cost Factors to Weigh
| Cost Factor | LP SmartSide | James Hardie |
|---|---|---|
| Material + install cost | Generally lower upfront | Generally higher upfront |
| Expected maintenance cost over 20 years | Higher — recoating, caulking, edge repairs | Lower — periodic caulk/paint upkeep only |
| Risk of localized board replacement | Moderate, tied to sealing quality and exposure | Low when installed to spec |
| Resale/appraisal perception | Solid, wood-look siding | Often viewed favorably for durability and fire rating |
What This Means for Your Project
We're not going to tell you LP SmartSide can't work anywhere — plenty of homes carry it without major issues, especially with diligent owners and drier microclimates. But as a company, we don't want to install a product on a Blaine or Birch Bay home, sell it as low-maintenance, and then watch salt air, driving rain, and moss season find every unsealed edge over the next decade. That's why fiber cement is the only siding system we put our name behind.
If you're weighing siding options for a home in Blaine, Birch Bay, or anywhere in Whatcom County, we're happy to walk your property, talk through what we see, and give you a straightforward, no-pressure estimate for a James Hardie installation — no sales pitch, just an honest look at your home and your options.