Bellingham Exterior A Straight Answer to a Question We Get Often
Homeowners in Bellingham ask us about LP SmartSide more than almost any other product, usually because a neighbor has it, a builder recommended it, or a big-box estimate came in lower than expected. It's a fair question, and it deserves a straight answer rather than a sales pitch. Bellingham Exterior Contractors installs James Hardie fiber cement exclusively. We don't install LP SmartSide, and this page explains why, using the same reasoning we'd use if you asked us across the counter.
This isn't about bashing a product line that millions of homes use without issue. LP SmartSide has real strengths, and we'll say so plainly. But our job is to put siding on Whatcom County homes that we're willing to stand behind for decades, in a climate that is genuinely harder on exterior building materials than most of the country realizes. That combination of standards led us to one product family, and it isn't LP SmartSide.
What LP SmartSide Actually Is
LP SmartSide is an engineered wood product — strand-based wood fiber (similar in concept to OSB) treated with resins, waxes, and zinc borate for insect and fungal resistance, then pressed into panels or lap boards and finished with a factory primer or overlay. It's lighter than fiber cement, easier to cut without special blades, and typically less expensive installed. For builders working on tight budgets in drier climates, it's a reasonable, code-compliant choice, and we're not going to pretend otherwise.
Where It Genuinely Performs Well
- Lower material and labor cost than fiber cement in most markets
- Lighter weight, which speeds up installation and reduces fastener load
- Impact resistance that holds up well to normal wear
- A manufacturer warranty that covers manufacturing defects for a defined term
The Core Issue: Wood Is Still Wood
Strip away the resin treatment and zinc borate, and LP SmartSide's core is still wood fiber. Wood fiber absorbs moisture. It swells, and if it stays wet long enough or repeatedly, it can soften, delaminate at cut edges, or invite rot at the points where water gets past the finish — typically bottom edges, butt joints, and anywhere caulking has failed. LP has improved the product significantly since the OSB-era failures of the 1990s that led to a large class-action settlement, and today's SmartSide with its resin-saturated strand technology is a materially better product than what gave engineered wood siding its bad reputation. We want to be fair about that history.
But "better than it used to be" is a different bar than "right for Bellingham." Whatcom County sits in a marine climate with persistent moisture: driving rain off the Salish Sea, long stretches of drizzle from fall through spring, and heavy moss and lichen growth on north- and shade-facing walls that hold dampness against the siding surface for weeks at a time. Engineered wood siding depends entirely on its factory finish and field-applied caulking staying intact to keep water out of the wood fiber core. In a dry climate, that finish degrades slowly. In ours, with UV exposure, driving rain, and salt-laden air near the water, caulk joints and cut-edge sealant need more frequent inspection and maintenance than most homeowners realize when they buy the product.
Installation Sensitivity: The Part Nobody Talks About
LP SmartSide's real-world performance is more installation-dependent than fiber cement's. Every cut edge has to be field-sealed with the correct primer or sealant before installation, every joint has to be properly caulked, and clearances at grade, roof lines, and trim have to be maintained precisely — because unlike fiber cement, this product doesn't tolerate standing water or wicking at an unsealed edge for long before damage starts. That's a lot of steps that have to be done right, every time, on every board, by every crew member, on every job.
We don't say this to cast doubt on other contractors' work. We say it because we know how hard it is to guarantee zero installation error across a full crew and a full siding job, especially over multiple years of jobs. Fiber cement gives us a wider margin for error at the cut edge and the joint, because the material itself doesn't absorb and swell the way wood fiber does. In a climate as wet as ours, we'd rather build in that margin than depend on perfect caulking holding up indefinitely.
Where the Trade-Off Shows Up Over Time
| Factor | LP SmartSide | James Hardie Fiber Cement |
|---|---|---|
| Core material | Engineered wood strand, resin-treated | Cement, sand, and cellulose fiber |
| Moisture response | Can swell or soften if finish/caulk fails | Does not swell, rot, or support fungal growth |
| Cut-edge treatment | Must be field-sealed with correct primer | Factory-finished; less field sealing required |
| Combustibility | Combustible (wood-based) | Non-combustible |
| Typical factory finish life | Varies; often 15-year finish warranty | ColorPlus finish, 15-year finish warranty on top of longer product warranty |
| Performance in prolonged wet/shaded exposure | Requires closer maintenance attention | More forgiving of moss, shade, and driving rain |
Moss, Shade, and North-Facing Walls
Bellingham's tree cover and cloud cover mean a lot of homes have walls that rarely see direct sun — under eaves, behind mature landscaping, on the north side facing a greenbelt. Those are the walls where moss and algae take hold first, and where a wall surface stays damp longest after a rain event. On an engineered wood product, that prolonged dampness sitting against the surface is exactly the condition that stresses the finish and, eventually, the substrate underneath. On fiber cement, sustained moisture and moss growth are a cosmetic and cleaning issue rather than a structural one, because there's no wood fiber underneath to feed on that moisture.
This is a genuinely regional consideration. A siding product that performs fine in Spokane's drier climate, or even in Seattle proper with less rain shadow effect, can be tested harder by Bellingham's specific mix of marine air, rainfall totals, and heavy tree canopy. We install what holds up to those specific conditions with the least ongoing maintenance burden for the homeowner.
Fire Consideration
It's worth stating plainly: LP SmartSide is a wood-based product and is combustible, even with its treatments. James Hardie fiber cement is non-combustible. Wildfire risk in Whatcom County is lower than in parts of Eastern Washington, but insurance underwriting increasingly factors exterior cladding material into wildfire-adjacent risk pricing, and non-combustible siding is a straightforward, honest advantage for anyone thinking about long-term insurability as underwriting standards tighten across the state.
Why We Standardized on James Hardie
We install James Hardie exclusively because it lets us make promises we can actually keep. It's a cement-based product, so it doesn't rot, doesn't feed fungal growth, and isn't vulnerable to the swelling and softening that moisture-stressed wood-based products can experience. It comes with a factory-applied ColorPlus finish backed by its own warranty, separate from the product warranty, so color and finish performance aren't riding entirely on field-applied paint. Hardie's HZ5 product line is engineered specifically for climates like ours — freeze-thaw cycling, sustained damp exposure, and coastal moisture — rather than being a general-purpose product stretched to fit every region.
None of that makes fiber cement maintenance-free — it still needs proper caulking at trim and penetrations, and paint touch-up eventually — but the baseline material is far less sensitive to the small installation and maintenance lapses that are inevitable on any real job, on any real house, over enough years.
What We Look For Before Recommending Full Replacement
- Soft spots, delamination, or swelling at seams and cut edges on existing engineered wood siding
- Persistent moss or algae buildup on shaded or north-facing walls
- Caulk failure or gaps at butt joints and trim
- Visible finish wear, chalking, or color fade beyond the finish warranty period
- Water staining on siding above grade or below roof lines
What This Means If You Already Have LP SmartSide
If your home currently has LP SmartSide and it's performing well, we're not going to tell you to rip it off preemptively. Well-installed engineered wood siding that's been properly maintained — caulk joints inspected, finish kept intact, moss cleaned off before it takes hold — can last for its intended service life. What we will tell you, honestly, is what to watch for: soft spots near the ground, swelling at panel joints, and any area where moss has sat undisturbed for more than a season. Those are the early signs worth having looked at before they become a full-wall problem.
When it does come time to reside, that's the point where we'll walk you through why we recommend Hardie fiber cement over another round of engineered wood, vinyl, or other alternatives — and let you weigh the trade-offs for your own home and budget.
Get a Straight Answer for Your Home
Every house and every wall exposure is a little different, and the right answer for a sun-exposed south wall isn't always the same as for a shaded north wall next to a greenbelt. If you're weighing siding options in Bellingham or anywhere in Whatcom County, we're happy to walk your property, point out what we actually see, and give you a free, no-pressure estimate — no obligation, no pressure toward any particular product.