Skagit County Two Very Different Materials Wearing the Same Job Title
When homeowners in Skagit County start pricing siding, they usually hear two names pop up more than any others: James Hardie fiber cement and LP SmartSide engineered wood. Both are marketed as durable, low-maintenance upgrades over vinyl or old cedar. Both come primed or pre-finished. Both are installed by reputable contractors across Western Washington. But underneath the marketing, they are fundamentally different products made from different raw materials, and that difference matters a lot once you're dealing with the specific weather this region throws at a house.
This page walks through what each product actually is, where LP SmartSide performs well, where it runs into trouble in our climate, and why we made the decision to install James Hardie exclusively rather than offer both.
What LP SmartSide Actually Is
LP SmartSide is an engineered wood product. It's manufactured from wood strands bonded with resins under heat and pressure, then coated with a wax-based moisture-resistant treatment and a primer layer. It's a legitimate step up from old-school hardboard siding, which had a rough history with moisture failure in the 1990s and early 2000s. LP has addressed a lot of those old problems with better resin systems and a proprietary treatment process (SmartGuard).
Where it does well:
- Lighter weight than fiber cement, which can mean faster installation and easier handling
- Easier to cut and work with standard woodworking tools, no silica dust concerns
- Looks and feels more like traditional wood siding to the touch
- Lower material cost than James Hardie in most markets
Those are real advantages, and for homeowners in drier climates, or for accessory structures that aren't taking the brunt of weather, LP SmartSide is a reasonable product installed by a lot of competent contractors.
Why We Don't Install It Here
The honest issue with LP SmartSide isn't the factory product on the day it's installed — it's what happens to it over 10, 15, 20 years in a climate like ours. Skagit County sits between Puget Sound and the Cascade foothills, which means siding here deals with three things at once: near-constant moisture from driving rain off the water, a moss and algae season that can run eight or nine months out of the year, and salt-laden air in the western parts of the county closer to the Sound and the San Juan approaches.
Engineered wood, no matter how well it's treated at the factory, is still wood at its core. Wood strands bonded with resin will absorb and release moisture at the cut edges, at fastener penetrations, and anywhere the factory coating gets breached — which happens routinely during a real-world installation with butt joints, corners, and trim intersections. Once moisture gets into an edge that isn't perfectly sealed and re-caulked on a maintenance schedule, the product can swell, delaminate at the strand layers, or invite rot from the inside out where you can't see it happening.
That failure mode is manageable in Eastern Washington or inland climates with real dry seasons. It's a much harder bet in a county where a wall can go weeks without a real drying stretch between November and April, and where moss holds moisture against the wall surface for months at a time. We've seen enough of this pattern in siding replacement work across the county to no longer offer engineered wood as an option we stand behind.
The Maintenance Commitment Is the Real Cost
LP SmartSide isn't a "set it and forget it" product. To hit its intended lifespan, every cut edge needs to be field-primed and caulked at install, and the caulking at joints, trim, and penetrations needs to be inspected and refreshed on a regular cycle — realistically every few years in a wet coastal climate. Skip that maintenance, or hire an installer who rushes the edge-sealing details, and you've shortened the product's real-world life significantly, often well before its warranty term is up.
How James Hardie Fiber Cement Is Built Differently
James Hardie siding is made from Portland cement, sand, and cellulose fiber, cured into a dense, stable board. There's no wood strand structure to swell, no organic material for rot fungus to feed on, and the material itself is non-combustible. It doesn't absorb water the way engineered wood does, and it doesn't need the same edge-sealing discipline to survive contact with moisture at a cut or joint.
James Hardie also engineers specific product lines for different climate zones — their HZ5 formulation is built for cold, wet regions like ours, with freeze-thaw performance and moisture behavior tuned for the Pacific Northwest rather than a one-size-fits-all national spec. The factory finish, ColorPlus Technology, is a baked-on finish applied and cured under controlled conditions, which holds color and resists fading, chipping, and cracking far better than field-applied paint — which matters here, since UV isn't the enemy so much as the constant wet-dry cycling that stresses paint film over time.
Side-by-Side Comparison
| Factor | James Hardie Fiber Cement | LP SmartSide Engineered Wood |
|---|---|---|
| Core material | Cement, sand, cellulose fiber | Wood strands bonded with resin |
| Moisture behavior | Dimensionally stable, does not swell or rot | Can swell, delaminate, or rot at exposed/unsealed edges |
| Fire rating | Non-combustible | Combustible (treated, but still wood-based) |
| Finish | Factory-baked ColorPlus finish, 15-year finish warranty in most cases | Factory primer; typically field-painted, shorter repaint cycle |
| Maintenance | Occasional wash; caulk inspection at joints | Regular edge-sealing, caulk renewal, repainting cycle |
| Moss/algae resistance | Good; surface doesn't feed organic growth | Fair; more prone to surface staining and edge moisture retention |
| Warranty | Long-term, transferable manufacturer warranty | Manufacturer warranty, often more exclusions tied to installation/maintenance |
| Material cost | Higher | Lower |
| Installation sensitivity | High — correct fastening, clearances, and flashing critical | High — edge sealing and joint treatment critical |
Installation Quality Matters for Both — But the Stakes Differ
It's worth being fair here: neither product is foolproof, and both fail early when installed poorly. Fiber cement that's face-nailed instead of properly fastened, installed too tight to the ground, or hung without correct flashing and clearances can crack, absorb water at the ends, or trap moisture behind the wall just like any other siding installed wrong. Good installation practice matters no matter what material goes on the wall.
The difference is what happens after a small installation gap or a missed maintenance cycle. On fiber cement, a slightly under-sealed cut edge is a cosmetic issue you can address later — the material itself isn't going to rot from that gap. On engineered wood, the same gap is the entry point for moisture into a wood-based product, and the clock starts running the day it's installed, not the day someone finally notices a problem.
Why We Standardized on James Hardie
We made the decision years ago to install James Hardie exclusively rather than offer a menu of siding materials. Part of that is climate — Skagit County's combination of driving rain off the Sound, long moss seasons, and salt air in the western half of the county rewards a material that doesn't depend on a perfect ongoing maintenance schedule to avoid moisture damage. Part of it is warranty — a strong, transferable manufacturer warranty backed by correct installation gives homeowners real protection, not just a document. And part of it is simply that we'd rather be excellent at one system, know its details cold, and stand behind it, than spread ourselves across several products with different failure modes and different maintenance requirements.
That doesn't mean LP SmartSide is a bad product installed by every contractor who offers it. It means we've drawn a line based on what holds up best, longest, with the least maintenance burden, in this specific climate — and that line points to fiber cement.
What to Ask Before You Choose a Siding Material
- How does this product perform when a cut edge or joint gets wet and isn't resealed right away?
- What's the manufacturer's actual maintenance schedule to keep the warranty valid — and is that realistic for you to keep up with?
- Is the warranty transferable if you sell the house, and what voids it?
- Is the finish factory-applied and baked on, or will you be responsible for repainting on a cycle?
- Does the installer have documented experience with this specific product's fastening and clearance requirements?
- How does the product handle moss and algae exposure on north-facing or shaded walls?
Get an Honest Look at Your Home
Every house in Skagit County carries its own mix of sun exposure, wind-driven rain, and moss risk depending on where it sits and how it's oriented. If you're weighing siding options and want a straight answer about what will actually hold up on your specific house, we're happy to take a look and walk you through it — no pressure, no sales script. Reach out for a free estimate and we'll give you our honest read.