Custer Two Very Different Materials, Both Called "Engineered Siding"
When homeowners in Custer start researching siding replacement, James Hardie and LP SmartSide come up together constantly. They're often marketed side by side as premium alternatives to vinyl, and on a spec sheet they can look similar — both come in lap, panel, and shingle profiles, both offer factory-applied finishes, and both are positioned as long-term siding systems. But they are fundamentally different products made from different materials, and that difference matters more here than in most parts of the country.
We install James Hardie fiber cement exclusively. That's a deliberate standard, not a default, and it's worth explaining honestly what LP SmartSide does well, where it runs into trouble, and why we don't put it on homes.
What LP SmartSide Actually Is
LP SmartSide is an engineered wood product — strand board made from wood fibers bonded with resin, then treated with a zinc-borate formula (LP calls it SmartGuard) to resist fungal decay and insects, and coated with a resin-saturated overlay for moisture resistance. It's a genuine improvement over old-school hardboard siding, which had a rough history with moisture failures in wet climates. LP SmartSide is lighter than fiber cement, easier and faster to cut and nail, and generally less expensive installed. For a lot of markets, it's a reasonable, cost-effective choice.
The catch is that it's still a wood-based product at its core. The treatments extend its resistance to moisture, but they don't change the fact that strand board swells if water gets past the surface and into the substrate — at a poorly sealed cut end, a fastener hole, a butt joint, or a spot where caulking has failed. Once moisture gets into the core, that's where the problems start: swelling, delamination at the edges, and softening that doesn't reverse itself.
Why That Matters More in Custer Than Almost Anywhere Else
Whatcom County isn't a climate that forgives sloppy moisture management. Custer sits close enough to the Salish Sea that salt-laden air is a constant factor, homes here take driving, wind-blown rain for months at a stretch, and the long, overcast moss season means north- and west-facing walls stay damp far longer than they would in a drier region. That combination — salt air, sustained rain exposure, and shaded, moisture-holding conditions that feed moss and algae growth — is exactly the environment where an engineered wood product's weak points get tested hardest.
It's not that LP SmartSide is a bad product everywhere. It's that its long-term performance depends heavily on installation precision (every cut edge properly sealed, every joint properly flashed) and on the homeowner keeping up with caulking and repainting on schedule for the life of the siding. In a climate that gives siding fewer dry weeks per year to shed moisture, that margin for error shrinks.
Where Fiber Cement Behaves Differently
James Hardie siding is a cement, sand, and cellulose fiber composite — there's no wood strand core to swell, rot, or delaminate if moisture reaches it. It doesn't expand and contract with humidity the way wood-based products do, which keeps joints and paint lines tighter over time. It's also non-combustible, which is a meaningfully different fire-safety category from a treated wood product, whatever the treatment.
Hardie's HZ5 product line is specifically engineered for climates with heavy moisture exposure, which is the reason it's the standard we build to in Whatcom County rather than a general-purpose or dry-climate formulation. The ColorPlus factory finish is baked on under controlled conditions and carries its own finish warranty, which takes the "repaint every several years or void your protection" burden off the homeowner in a way site-applied or lighter factory finishes typically don't.
Comparing the Two, Side by Side
| Factor | James Hardie (fiber cement) | LP SmartSide (engineered wood) |
|---|---|---|
| Core material | Cement, sand, cellulose fiber | Wood strand board with resin binder |
| Combustibility | Non-combustible | Combustible (treated, not fireproof) |
| Moisture behavior | Doesn't swell or delaminate | Can swell/delaminate if moisture reaches core |
| Finish | Factory-baked ColorPlus, separate finish warranty | Factory or site-applied, standard repaint cycle |
| Installation sensitivity | Moderate — sealing and fastening to spec matters | High — every cut/edge/joint must be sealed properly |
| Weight/handling | Heavier, more crew-intensive | Lighter, faster to install |
| Typical warranty structure | Long-term, transferable, non-prorated on siding substrate | Varies by line, often maintenance-conditional |
Our Standard, Plainly Stated
We don't install LP SmartSide, vinyl, or other wood-based composite siding — not because those products can't perform when installed and maintained perfectly, but because "installed and maintained perfectly for 30+ years" isn't a bet we're willing to make on a client's behalf in a climate this consistently wet. James Hardie fiber cement gives us a material that doesn't depend on a flawless maintenance schedule to avoid moisture damage, and that's the standard we want backing every job with our name on it.
If you're weighing siding options for a home in Custer or elsewhere in Whatcom County, we're happy to walk through what we see in this climate and answer questions honestly — no pressure, no obligation. Reach out for a free estimate and we'll take a look at your home's specific exposure and talk through what makes sense.