Ferndale Siding Two Different Materials, One Big Decision
If you're re-siding a home in Ferndale, you've likely run into two products competing for your attention: James Hardie fiber cement and LP SmartSide engineered wood. Both are marketed as durable, low-maintenance upgrades over vinyl or aging cedar. Both look good on a spec sheet. But they are fundamentally different materials, and in Whatcom County's climate — with its salt air pulling in off Bellingham Bay, driving winter rain, and a moss season that can stretch from October through May — that difference matters more than most homeowners realize before they've lived with the siding for a few years.
We install James Hardie fiber cement exclusively. We don't install LP SmartSide, vinyl, or other engineered wood products. This page explains what each material actually is, where LP SmartSide holds up and where it struggles in our specific climate, and why we standardized on Hardie for the homes we work on.
What LP SmartSide Actually Is
LP SmartSide is an engineered wood product — strand board made from wood fibers, resin, and wax, pressed under heat and coated with a resin-saturated overlay for weather resistance. It's a genuine improvement over old-style OSB siding, and LP backs it with a reasonable warranty and treats it against fungal decay at the factory. In dry to moderate climates, it performs well for a long time.
The catch is that it's still wood at its core. Wood, treated or not, absorbs moisture. LP SmartSide is engineered to resist that better than raw lumber, but "resist" isn't "immune." Any wood-based product depends heavily on an intact factory coating and correct field caulking at every joint, seam, and penetration to keep water out over decades. Where that coating gets compromised — a scratch, a nail pop, a poorly sealed butt joint — moisture has an entry point, and wood fiber is exactly the kind of material that swells, delaminates, and eventually rots once water gets behind or into it.
What James Hardie Fiber Cement Actually Is
James Hardie siding is made from cement, sand, and cellulose fibers, cured into a rigid board. There's no wood fiber for moisture to attack and no organic material for fungus or insects to feed on. It doesn't swell, delaminate, or rot the way wood-based products can. It's also non-combustible, which matters more every year as wildfire smoke and dry summer stretches become a bigger part of Pacific Northwest life, even here on the wetter west side of the Cascades.
Hardie's HZ5 product line is engineered specifically for climates like ours — regions with sustained damp conditions and freeze-thaw cycling. The ColorPlus factory finish is baked on and warranted separately from the substrate, which reduces the repaint cycle that wood and fiber-cement-without-ColorPlus both require.
Where Ferndale's Climate Changes the Calculation
Salt Air and Coastal Exposure
Ferndale sits close enough to Bellingham Bay and the Strait of Georgia that airborne salt is a real factor on exterior materials, especially on homes with west or northwest exposure. Salt accelerates the breakdown of coatings and metal fasteners, and it can work into any small crack or seam faster than plain rainwater would. Fiber cement's rigid, non-porous composition holds up to that exposure with far less long-term coating failure than a wood-based substrate.
Driving Rain
Whatcom County doesn't just get a lot of rain — it gets wind-driven rain off the water, which pushes moisture sideways into siding laps, corners, and trim joints that vertical rain would never reach. Any siding material can leak if it's installed wrong. But when a small installation flaw does let water in, the consequence is very different depending on what's behind the coating. Water against fiber cement doesn't cause structural swelling. Water that reaches wood fiber, even engineered wood fiber, starts a clock.
Moss Season
Our extended moss season — often eight months of the year on shaded, north-facing walls — means siding stays damp for long stretches at a time, not just during storms. Moss and algae growth on siding isn't cosmetic in the long run; it holds moisture against the surface. Fiber cement's inorganic makeup doesn't feed biological growth the way wood fiber can, and it tolerates the periodic pressure-washing or gentle cleaning that moss removal requires without the surface degradation that repeated cleaning can cause on a wood-based product.
Side-by-Side Comparison
| Factor | James Hardie Fiber Cement | LP SmartSide |
|---|---|---|
| Core material | Cement, sand, cellulose fiber | Engineered wood strand board |
| Moisture behavior | Does not swell or rot; moisture is a coating/finish issue only | Wood fiber can swell, delaminate, or decay if water reaches it |
| Combustibility | Non-combustible | Combustible (wood-based) |
| Salt air / coastal durability | Strong; inorganic substrate resists degradation | Coating and treated wood provide protection, but substrate is more vulnerable if compromised |
| Moss / algae resistance | Inorganic surface, doesn't feed growth | More susceptible to surface staining and biological growth over time |
| Finish/warranty structure | Factory ColorPlus finish, separately warranted, long repaint interval | Factory primed or pre-finished depending on product; standard repaint cycle applies |
| Installation sensitivity | High — requires correct fastening, clearances, and caulking to spec | High — requires correct sealing at every joint and cut edge |
| Typical lifespan when installed correctly | Multiple decades, often exceeding original ownership | Solid performance in the right conditions; more climate- and maintenance-dependent |
Installation Is Where Both Products Live or Die
It's worth being honest about something: a poorly installed Hardie job can fail too, and a well-installed LP SmartSide job can perform for many years. Material choice doesn't override workmanship. Every cut edge on fiber cement needs to be sealed or back-primed. Every seam on engineered wood needs correct caulking and the factory finish needs to stay intact. Flashing, ventilation gaps behind the siding, and correct fastener depth matter on both products.
Where we've drawn the line is this: fiber cement gives a wider margin for error over time. If a caulk joint fails on an LP SmartSide wall and goes unnoticed for a season or two in our rain, the consequence can be structural damage to the siding itself. The same failure on fiber cement is far more likely to remain a cosmetic or moisture-management issue rather than a material integrity issue. In a climate that gives siding as little downtime to dry out as Whatcom County does, we'd rather build in that margin from the start.
Cost Considerations
LP SmartSide typically costs less upfront than James Hardie fiber cement, both in material and sometimes in labor. That's a real, legitimate factor for a lot of homeowners, and we won't pretend otherwise. The comparison that matters more, though, is cost over the life of the siding — including repainting cycles, caulk maintenance, moss cleaning frequency, and the risk of localized repair or replacement if moisture does find its way in. Fiber cement's higher upfront cost is generally offset by a longer maintenance-light interval and a stronger, more transferable warranty structure.
What to Ask Before You Choose
- What does the manufacturer's warranty actually cover — material only, or labor too — and is it transferable if you sell the home?
- Is the product rated for your specific climate zone, or a general-purpose version?
- What's the manufacturer's documented field-cutting and sealing requirement, and will your contractor follow it on every board?
- How is the product expected to perform after 15-20 years of driving rain and salt air exposure specifically in a coastal Whatcom County setting?
- What's the realistic repaint or recoat interval, and what does that cost over time?
- Does your contractor install this product every day, or occasionally? Installation consistency affects long-term performance as much as the material itself.
Why We Standardized on James Hardie
We made a decision as a company to install one fiber cement system rather than juggle multiple siding materials, and James Hardie is that system. It's non-combustible, it doesn't carry the moisture-related failure modes that any wood-based product carries, and the HZ5 line is built for exactly the sustained-damp, salt-exposed, moss-prone conditions Ferndale sees for most of the year. The ColorPlus finish reduces the repaint burden, and the warranty structure gives homeowners real protection rather than a material-only guarantee with gaps.
That's not a knock on every engineered wood product on the market — LP SmartSide has a legitimate place in drier regions and on projects where budget is the deciding factor. It's simply that when we look at what performs best, with the fewest surprises, on homes exposed to a Pacific Northwest coastal climate year after year, fiber cement is what we're willing to put our name behind.
Get a Straight Answer for Your Home
Every house is different — sun exposure, wall orientation, existing moisture issues, and your own priorities all factor into the right siding decision. If you'd like a straightforward, no-pressure look at your home and an honest recommendation, request a free estimate below.