Custer A Straightforward Answer to a Question We Get Often
Homeowners in Custer and across Whatcom County ask us about LP SmartSide more than almost any other product. It's a well-marketed engineered wood siding, it's available through a lot of lumber yards, and plenty of contractors install it. We don't. This page explains why, without exaggerating the product's downsides or pretending it's junk. It isn't junk. It's a product with a specific set of trade-offs that, in our professional judgment, don't hold up as well as fiber cement in the exact climate we work in.
Our position is simple: we install James Hardie fiber cement siding exclusively. Not because we have something against engineered wood as a category, but because after years of exterior work in this region — salt air drifting in off the Salish Sea, driving rain off the water, and a moss season that seems to stretch longer every year — we've settled on the product system that holds up best with the least long-term maintenance.
What LP SmartSide Actually Is
LP SmartSide is an engineered wood product. It's made from wood strands or wood fiber, bonded with resins and waxes, then treated with a zinc-borate compound for insect and fungal resistance. It comes in lap siding, panel siding, and trim configurations, and it's designed to be easier to cut and handle than fiber cement — lighter, and workable with standard woodworking blades rather than specialized fiber cement tools.
What It Gets Right
To be fair to the product: LP SmartSide holds paint well, it's lighter to handle on a job site, and the zinc-borate treatment is a real improvement over untreated wood siding from decades past. For a contractor working in a dry climate, or on a budget-driven project where the owner understands the maintenance commitment, it can be a reasonable choice. It is not a scam product or a product we'd call unsafe.
Where It's Still Wood
The core of LP SmartSide is still wood fiber. That means the entire performance of the product — for its full service life — depends on the wood staying dry. Wood that stays dry lasts. Wood that gets and stays wet, doesn't, no matter what treatment is in the strands. That single fact drives almost everything else on this page.
Why Moisture Management Is the Whole Ballgame
Every siding product has an Achilles' heel. For engineered wood, it's moisture intrusion at the places where the factory finish can't protect the material: field cuts, fastener penetrations, and joints. When a crew cuts a panel to fit around a window or a corner, that cut edge exposes raw wood fiber. If it isn't sealed correctly, with the right sealant, every time, on every cut, on every job — that's the point where water gets in.
The Role of Edge Sealing and Field Cuts
Manufacturers of engineered wood siding are explicit in their installation instructions that all field-cut edges must be primed or sealed before installation. This is not optional in their own literature. In our experience walking past other contractors' completed jobs and doing repair estimates on older installations, this step is one of the most commonly skipped or rushed details in siding work generally — not because installers are careless, but because it's a slow, unglamorous step that's easy to shortcut on a schedule, and the consequences don't show up for a few years.
With fiber cement, a missed seal on a field cut is a cosmetic issue. With engineered wood, it's the beginning of a moisture problem that can telegraph through the finish, cause swelling at the cut line, and eventually lead to rot that isn't visible from the outside until it's advanced.
Custer's Climate Doesn't Give Installation Mistakes Room to Hide
This is the part of the equation that's specific to where we work, not a generic knock on the product. Custer sits in Whatcom County close enough to the water that salt-laden air is a routine part of the exterior environment, and the Pacific storm track sends driving, wind-blown rain against north and west-facing walls for a large part of the year. Add a moss season that runs long in the shaded, damp conditions common here, and you have a climate that finds every gap in a building envelope faster than a drier region would.
In a place like eastern Washington, an occasional missed seal or a slightly undersized gap might sit fine for a decade. In Whatcom County, moisture has more opportunities per year to find its way into a vulnerable edge, and once wood fiber siding takes on water, moss and mildew have an easier time establishing themselves on top of it. We'd rather build in a wider margin for error than count on flawless caulking and sealing at every single field cut, forever, on every home we touch.
Where We've Seen Engineered Wood Struggle Locally
On repair and re-side estimates around Whatcom County, the patterns we see most with older wood-based siding products — engineered and otherwise — are consistent: swelling and soft spots at butt joints and cut ends, paint failure where water has gotten behind the finish, and moss or algae staining on north-facing and shaded walls where surfaces stay damp longer. None of this means the product was defective. It usually means moisture found a way in through an installation detail, and once wood fiber is wet, drying it back out in our climate is a slow process that doesn't always finish before the next rain.
The Warranty Fine Print Worth Reading
Most engineered wood siding manufacturers offer a solid-looking warranty on paper, but like most building product warranties, it's conditioned on installation exactly to spec — correct clearances, correct fastening, correct sealing of every cut edge, correct flashing details. If an installer skips a step, the manufacturer's inspection process (should a claim ever be filed) can trace the failure back to the installation rather than the material, and the warranty coverage narrows or disappears. That's not unique to LP — it's standard across the industry, including fiber cement. But it matters more for a moisture-sensitive wood product than for a product that isn't harmed by getting wet in the first place.
LP SmartSide vs. James Hardie: The Honest Comparison
| Factor | LP SmartSide (Engineered Wood) | James Hardie (Fiber Cement) |
|---|---|---|
| Core material | Wood strand/fiber with resin binder | Cement, sand, and cellulose fiber |
| Behavior when wet | Can swell, soften, or rot if moisture gets past the finish | Does not rot, swell, or support fungal growth |
| Fire performance | Combustible wood-based material | Non-combustible |
| Field-cut sensitivity | High — every cut must be sealed per manufacturer spec | Lower — cut edges are not moisture-vulnerable the same way |
| Factory finish | Primed or factory-coated, repaint intervals vary | ColorPlus baked-on finish, longer intervals between repaints |
| Typical weight/handling | Lighter, easier for a crew to move and cut | Heavier, requires fiber-cement-rated tools and blades |
| Insect resistance | Zinc-borate treated | Not a food source for insects — non-organic core |
Why We Standardized on James Hardie
We made the decision to install James Hardie fiber cement exclusively because it removes the single biggest variable in the moisture equation: the material itself doesn't rot, swell, or feed fungal growth, even if a sealing detail somewhere isn't perfect. That doesn't mean installation quality stops mattering — flashing, gapping, and fastening still have to be done right on any siding job — but the consequences of a small miss are far less severe.
ColorPlus Factory Finish
Hardie's ColorPlus finish is baked on in a controlled factory environment rather than field-applied, which gives more consistent coverage and generally holds color longer than a job-site-applied coating, meaning fewer repaint cycles over the life of the siding.
Climate-Engineered HZ Product Lines
James Hardie makes region-specific formulations (their HZ5 line, engineered for wetter, more humid climates) rather than a single one-size-fits-all product. For a moss-prone, high-rainfall area like Whatcom County, that regional engineering is a meaningful advantage over a product line that isn't differentiated by climate zone.
Non-Combustible Core
Fiber cement's non-combustible composition is also simply a safer material to put on a home, independent of the moisture conversation.
What Correct Installation Actually Requires
Whichever siding product a homeowner chooses, installation quality is what separates a 30-year exterior from a 10-year headache. Before hiring any contractor for a siding project, it's worth asking about the following:
- Are they manufacturer-certified or factory-trained on the specific product they're proposing?
- Will they seal every field-cut edge, and can they explain their process for doing it?
- What house wrap and flashing details will they use behind the siding, not just the siding itself?
- What clearance will they leave at grade, decks, and roof lines to keep the bottom edge of the siding away from standing water?
- What does the manufacturer's warranty actually require to stay valid, and will the contractor put the installation details in writing?
- Do they have a plan for ventilation and drainage behind the cladding, given how much rain this area sees?
Making the Right Call for Your Home
We're not going to tell a Custer homeowner that LP SmartSide will fail on their house — plenty of installations, done carefully, hold up fine for years. What we will say is that we've chosen not to put our name behind a moisture-sensitive wood product in a climate this consistently wet, salt-touched, and moss-friendly, when a non-combustible, climate-engineered alternative exists and performs better with less ongoing maintenance. That's a professional standard we hold to on every job, not a sales pitch built around one product.
If you're weighing siding options for a home in Custer or anywhere else in Whatcom County, we're happy to walk your property, look at your specific exposure — sun, shade, wind direction, drainage — and give you a straight answer about what will actually hold up. Reach out for a free, no-pressure estimate and we'll talk through what makes sense for your house.