Anacortes Siding LP SmartSide Isn't a Bad Product — It's the Wrong Product for This Coast
We get asked about LP SmartSide often enough that it's worth explaining our position plainly. LP SmartSide is a legitimate, widely used engineered wood siding product. It's not a scam, it's not poorly made, and plenty of contractors install it well and stand behind it. Our decision to leave it off our install list isn't about the product being junk — it's about matching a siding system to what Anacortes and the rest of Skagit County actually throw at a house year-round: salt-laden marine air off Rosario Strait and Guemes Channel, long stretches of driving rain, and a moss and mildew season that can run eight months or more in shaded, north-facing exposures.
We install James Hardie fiber cement siding exclusively. This page explains the specific trade-offs behind that call, not a sales pitch dressed up as education.
What LP SmartSide Actually Is
LP SmartSide is an engineered wood product — strand board (similar in concept to OSB) that's treated with zinc borate for insect and fungal resistance, then resin-saturated and coated with a wax or overlay finish. It's manufactured to be more moisture-resistant than untreated plywood or dimensional lumber siding, and in dry-to-moderate climates it performs reasonably well when installed and maintained correctly.
Its strengths are real:
- Lighter and easier to handle on-site than fiber cement, which can speed up labor on some jobs
- Accepts paint well and has a wood-grain or smooth texture that reads as traditional siding
- Lower material cost than premium fiber cement in most markets
- Better impact resistance than vinyl
None of that is in dispute. The issue is what happens to an engineered wood product over 15-20 years in a wet, salt-exposed marine climate — and what that means for a homeowner's maintenance schedule and long-term cost.
The Core Difference: Wood Fiber vs. Fiber Cement
Every siding material eventually comes down to how it behaves at the edges — the cut ends, the seams, the fastener penetrations, the bottom courses near grade — because that's where water finds its way in. LP SmartSide's core is still fundamentally wood strand and resin. Even with borate treatment and a factory finish, any breach in that finish (a scuff during install, a nail split, a poorly sealed cut end, years of UV and rain wearing the coating thin) exposes wood fiber to moisture. Wood fiber that gets wet and stays wet swells, and swelling that happens repeatedly over freeze-thaw and wet-dry cycles is what eventually causes edge softening or delamination.
James Hardie fiber cement is cellulose fiber, sand, cement, and water, autoclaved into a rigid, dimensionally stable board. It doesn't have an organic wood core to swell, rot, or feed fungal growth. It's also non-combustible, which matters increasingly for insurance underwriting in Washington regardless of wildfire zone. The trade-off is that Hardie is heavier, more labor-intensive to install correctly, and typically costs more up front — which is exactly why installation quality and long-term maintenance are the two places this decision actually gets decided.
Why Anacortes' Specific Climate Raises the Stakes
Anacortes sits right on the water, and houses here take on a combination of exposures that inland Skagit County homes don't see as intensely:
- Salt air corrosion — airborne salt accelerates the breakdown of caulking, fasteners, and factory coatings faster than it would 20 miles inland
- Driving rain off the Strait — wind-driven rain pushes water horizontally into lap joints and seams that a calmer climate wouldn't stress as hard
- Extended moss and mildew season — shaded north and east elevations under mature evergreens stay damp for months, and organic growth on a wood-fiber surface isn't just cosmetic, it holds moisture against the material
Any siding product can be engineered to resist one or two of these. What we look for is a product that shrugs off all three at once, for decades, with minimal upkeep — because most homeowners don't want a siding system that demands a strict recoating and caulking schedule to stay ahead of moisture intrusion.
Where the Maintenance Burden Actually Shows Up
This is the part that doesn't get talked about enough at the point of sale. Engineered wood siding manufacturers, including LP, are explicit in their installation and warranty documentation about required maintenance: field-cut ends must be primed and sealed before installation, exposed fasteners and joints need caulk maintained over time, and the factory finish needs to be inspected and touched up on a regular interval — often every few years depending on exposure. Skip that maintenance in a wet marine climate and the warranty coverage itself can be affected, separate from whether the siding is visibly failing yet.
For a homeowner in a drier region, that maintenance cadence is a manageable chore. For a home a few blocks from the water in Anacortes, with rain hitting the walls sideways for months at a stretch, that same maintenance schedule becomes the difference between a siding job that looks good at year 15 and one that needs partial replacement.
Fiber cement isn't maintenance-free either — it still needs caulking at joints and periodic inspection — but there's no organic core to protect from moisture intrusion, so a missed caulk cycle is a cosmetic problem rather than a structural one.
Installation Sensitivity — Where Most Problems Actually Start
To be fair to the product, a lot of the engineered-wood siding failures we've seen called out in the industry trace back to installation, not the material itself. LP SmartSide's warranty coverage depends heavily on manufacturer-spec details being followed exactly:
| Installation detail | Why it matters for engineered wood |
|---|---|
| Field-cut end sealing | Unsealed cut ends expose raw wood strand directly to moisture — the single most common failure point |
| Minimum ground clearance | Splashback from grade or hardscape keeps the bottom courses chronically damp |
| Fastener placement and type | Wrong nail pattern or corrosion-prone fasteners can split panels or fail early in salt air |
| Flashing and joint sealant | Every lap and butt joint is a potential water entry point that needs correct detailing |
| Panel gap and expansion allowance | Wood-based panels move with moisture; tight installs can buckle or crack |
Fiber cement has its own installation-sensitive details — clearances, fastener spacing, joint treatment — but it has far more tolerance for the small field errors that inevitably happen on a real job site, because the material itself isn't racing to absorb water the moment a detail is missed.
What We Install Instead: James Hardie
We standardized on James Hardie fiber cement for every job we take on, and it comes down to a short list of things that matter most in this climate:
- Non-combustible core — cement-based, not wood-based, so there's no organic material to rot, swell, or feed moss and mildew growth
- ColorPlus factory finish — a baked-on finish engineered for UV and moisture resistance, backed by its own finish warranty separate from the product warranty
- Climate-engineered HZ product lines — Hardie manufactures HZ5 boards specifically formulated for wetter, harsher climate zones like ours in the Pacific Northwest
- Strong transferable warranty — coverage that holds up through a home sale, which matters given how often coastal Skagit County homes change hands
- Proven long-term performance — decades of installations in wet coastal and marine climates with a well-documented track record
It costs more to buy and more to install correctly. We think that's the honest trade, and it's why we don't offer LP SmartSide as an alternative — we'd rather turn down a job than install something we don't think will hold up on an Anacortes exterior for the long haul.
Questions Worth Asking Before You Choose a Siding Material
Whatever material you land on, and whichever contractor you hire, these are the questions that actually separate a good long-term decision from a regretted one:
- What is the material's core made of, and how does it behave when it gets wet?
- What maintenance schedule does the manufacturer require to keep the warranty valid?
- Does the warranty transfer to a new owner if you sell the home?
- Is the product rated or formulated for a marine or high-moisture climate zone specifically?
- What installation details most commonly cause failures or warranty denials with this product?
- Will the contractor put the manufacturer's installation spec in writing as part of the contract?
Get a Straight Answer for Your Home
Every house on this stretch of coastline has its own exposure — how close to the water it sits, how much shade and moss buildup it deals with, what direction the weather hits it from. We'd rather walk your property and give you a straight assessment than push a one-size-fits-all answer. If you're planning a siding project in Anacortes or anywhere in Skagit County, reach out for a free, no-pressure estimate — we'll tell you what we'd actually do on your home and why.