Bellingham Siding What LP SmartSide Actually Is
LP SmartSide is an engineered wood siding product made from wood strands bonded with resin, then treated with LP's proprietary SmartGuard process (a zinc-borate-based treatment meant to resist fungal decay and insects) and finished with a factory primer. It's manufactured in lap, panel, and trim profiles, and it's been on the market long enough to have a real track record — both good and bad — across the Pacific Northwest.
We want to be upfront about something: LP SmartSide is not a scam product, and plenty of contractors install it well. This page isn't about telling you it's junk. It's about explaining, honestly, why our crew standardized on James Hardie fiber cement instead, and why we think that decision matters more here in Bellingham than it might in a drier climate.
What LP SmartSide Gets Right
Credit where it's due. SmartSide has a few real advantages that matter to homeowners:
- Weight and workability — it's significantly lighter than fiber cement, which can mean faster installs and less strain on the framing crew.
- Impact resistance — engineered wood strand product tends to hold up well against hail, thrown debris, and the occasional ladder bump.
- Familiar tools — carpenters can cut and nail it with standard wood-siding techniques, without the diamond blades and dust control fiber cement requires.
- Cost — it typically lands below fiber cement and above vinyl on a per-square-foot basis, which makes it attractive on a tighter budget.
If those trade-offs line up with a homeowner's priorities and they've got a contractor who will maintain the caulking and paint schedule diligently, SmartSide can perform reasonably. Our concern isn't with the product in a vacuum — it's with how it behaves over a 20-30 year window on a house in Whatcom County specifically.
How the Product Is Actually Built
Under the primer, SmartSide is still wood — strands of wood fiber pressed and bonded with resin, not a solid wood board. The SmartGuard treatment is designed to keep moisture and insects from breaking that resin bond down over time. That treatment works as engineered as long as the factory-applied face coating and the field-applied paint and caulk stay intact. The moment water finds a way past that barrier — through a cut edge that wasn't primed, a caulk joint that failed, or a fastener that backed out — you're no longer dealing with a moisture-resistant product. You're dealing with wood strand and resin sitting wet.
The Maintenance Reality Nobody Loves Talking About
This is the heart of it. LP SmartSide is not a "install it and forget it" product. It's a primed substrate that needs field maintenance to keep performing:
- Cut ends and factory edges need to be primed or sealed on-site during installation — every single one, every time.
- Caulk joints at seams, trim, and penetrations need to be inspected and refreshed on a regular cycle, typically every few years.
- The topcoat paint needs repainting on a schedule most manufacturers put at 8-10 years, sooner in harsh exposures.
- Any chip, scratch, or gap that exposes raw substrate needs to be caught and sealed before the next wet season, not left for "next summer."
For a homeowner who stays on top of that schedule, SmartSide can go the distance. But most people don't repaint and re-caulk siding every few years — they repaint when it looks bad, which by then may already mean moisture has been working its way into seams for a season or two. The product's long-term performance is tied directly to a maintenance discipline that's hard to guarantee over decades of different owners, different budgets, and different priorities.
Why Whatcom County's Climate Raises the Stakes
Every siding product has a climate it's more or less forgiving in. Bellingham isn't that climate for an engineered wood product. A few specifics:
- Rain volume and duration — Whatcom County sees roughly eight or nine months a year of some rain, much of it the slow, saturating kind rather than short downpours. Siding here doesn't get a long dry season to fully purge moisture between wet spells.
- Driving rain off the Strait and Bay — wind-driven storms push water sideways into lap joints, trim intersections, and butt seams — exactly the spots where a caulk failure on SmartSide becomes a moisture entry point.
- Salt air — homes closer to Bellingham Bay and the water deal with airborne salt that accelerates the breakdown of caulk, fasteners, and paint film faster than an inland home would see.
- Moss and mildew season — the same damp, shaded conditions that grow moss on roofs and north-facing walls create a near-constant film of organic moisture against siding, which is worse for a wood-based product than for a mineral-based one.
None of that means SmartSide will fail on every house. It means the margin for maintenance error is thinner here than it would be in Spokane or Sacramento, and the consequence of a missed caulk cycle is a longer, wetter exposure window before anyone notices.
Installation Sensitivity
SmartSide's real-world performance depends heavily on installation discipline — more so than a lot of homeowners realize when they're comparing quotes. Proper clearance off grade and roof lines, correct fastener placement and depth, back-priming or sealing every field cut, and consistent caulking at every joint all have to happen correctly, every time, on every wall. Skip one of those steps on one panel and you've created a weak point that may not show a problem for a few years — long after the installer has moved on to the next job. We're not comfortable putting our name on a product where a single missed caulk line can quietly turn into a moisture problem five years down the road.
Warranty Structure: What You're Actually Covered For
| Factor | LP SmartSide (typical) | James Hardie Fiber Cement |
|---|---|---|
| Core material | Engineered wood strand + resin | Portland cement, sand, cellulose fiber |
| Combustibility | Combustible (wood-based) | Non-combustible |
| Factory finish | Primed; field paint required | ColorPlus factory-baked finish available |
| Field maintenance | Caulk & repaint on a recurring cycle | Caulk inspection; repaint optional, not required |
| Moisture sensitivity if breached | Wood substrate can swell/decay | Cement substrate does not rot |
| Typical warranty | Limited, often prorated after early years | Long-term, non-prorated on material |
The warranty gap matters as much as the material gap. A prorated warranty means the coverage you actually collect on shrinks the longer you own the house — which is exactly when a moisture-related failure is most likely to show up. Read any warranty document closely, including ours, before treating it as a safety net.
Cost Isn't the Whole Story
We won't pretend fiber cement is the cheaper option upfront — it isn't. SmartSide's lower material and labor cost is real and it's a legitimate reason some homeowners choose it. Where the math shifts is over a 20-30 year ownership window: recurring repaint cycles, caulk maintenance, and the risk of localized repair or replacement if moisture gets past the coating all add cost and hassle that don't show up on the initial quote. For a homeowner planning to sell within five years, that gap may never matter to them personally. For someone planning to stay in the home long-term, it usually does.
Why We Install James Hardie Instead
We made a decision a while back to install only James Hardie fiber cement siding, and it comes down to a simple standard: we want to hand a homeowner a wall system that doesn't depend on a perfect maintenance schedule to keep performing. Hardie's fiber cement is non-combustible, doesn't have a wood substrate that can swell or decay if a caulk joint eventually fails, and the ColorPlus factory finish line removes field-painting from the maintenance equation almost entirely. The HZ5 product line is engineered specifically for the kind of freeze-thaw, moisture-cycling climate we have in this part of Washington, and the transferable warranty backing it doesn't erode the way a prorated warranty does.
We're not installers who chase the lowest bid job to job — we install one system, correctly, and stand behind it. That's a narrower business than offering every product on the market, but it's the standard we're comfortable putting our name on for a Whatcom County home.
A Quick Checklist If You're Comparing Bids
- Ask what substrate the siding is built from, not just the brand name.
- Ask what maintenance schedule the manufacturer actually requires to keep the warranty valid.
- Ask whether the warranty is prorated, and at what year the coverage starts declining.
- Ask how the installer handles cut-edge sealing and caulk joints on your specific job — get it in writing.
- Ask what happens if moisture gets behind the siding — is the fix a spot repair or a wall-section tear-off?
The Bottom Line
LP SmartSide isn't a bad product — it's a maintenance-dependent product, and Bellingham's rain, salt air, and moss season don't leave much room for that maintenance to slip. We'd rather install a siding system that's forgiving of the real-world gap between what a warranty assumes and what actually happens over 20 years of Pacific Northwest weather. If you're weighing your options for a siding replacement or new build, we're happy to walk through what we install, why, and how it would perform on your specific home. Reach out for a free, no-pressure estimate — there's no obligation, and we'll give you the same straight answers you just read here.