Bellingham Exterior Two Fiber Cement Boards, Two Different Companies Standing Behind Them
Homeowners in Bellingham researching siding replacement eventually run into a question that doesn't get asked enough: if two products are both called "fiber cement," why does the contractor only install one of them? Cemplank and James Hardie siding are both fiber cement — a blend of cement, sand, and cellulose fibers pressed into planks and panels. On paper, that makes them look interchangeable. In practice, they are not the same product, made by the same process, or backed the same way. We get asked about Cemplank often enough, usually by homeowners comparing bids, that it's worth laying out exactly where the two diverge and why we made the call to install only James Hardie on Whatcom County homes.
This isn't a knock on fiber cement as a category — we think it's the right siding material for this climate, full stop. The question is which manufacturer's version of it we're willing to put our labor and our name behind.
What Cemplank Gets Right
Cemplank, manufactured by Nichiha, is a legitimate fiber cement product, not a knockoff. It resists fire, rot, and insects the way fiber cement is supposed to, and it holds paint better than wood lap siding. For a homeowner shopping strictly on upfront material price, Cemplank often comes in lower than James Hardie, and some contractors are comfortable installing it. We're not disputing that it can perform as a functional siding product when installed correctly. Where we part ways is in the details underneath that surface-level similarity — the factory finish, the climate engineering, the warranty backing, and the track record of the company standing behind the board twenty years from now.
Where the Two Companies Diverge
Factory-Applied Finish vs. Field-Applied Paint
James Hardie's ColorPlus finish is baked on in a controlled factory environment, cured before the board ever leaves the plant, and backed by its own separate finish warranty. That matters more in a place like Bellingham than it does in a dry inland climate, because factory-cured finishes resist the fading, chalking, and peeling that field-applied paint struggles with under repeated wet-dry cycling. Cemplank is available primed or factory-finished depending on the product line, but the finish systems and warranty backing are not structured the same way, and not every installer sources the factory-finished version — some jobs still end up painted on site, which reintroduces all the maintenance issues fiber cement siding is supposed to eliminate.
Climate-Engineered Product Lines
James Hardie builds region-specific formulations — HZ5 for the Pacific Northwest — engineered around the freeze-thaw cycles, driving rain, and prolonged damp exposure this coastal corner of Washington deals with every winter. That's not marketing language; it reflects a different mix and manufacturing process depending on climate zone. Cemplank does not offer that same tier of regional engineering across its lineup, which means the board going on a home in Bellingham isn't necessarily formulated any differently than one going on a house in a dry, low-humidity market.
Warranty Structure Side by Side
Warranty length looks similar on a spec sheet, but the structure and how a claim actually gets honored is where the real difference shows up. Transferability, what's prorated, and whether the finish is covered separately from the substrate all change the real-world value of the paper.
| Factor | James Hardie | Cemplank |
|---|---|---|
| Substrate warranty | Long-term, non-prorated for the original and often transferable to subsequent owners | Warranty exists but terms and transferability vary by product line |
| Finish warranty | Separate ColorPlus finish warranty, factory-backed | Finish coverage depends on whether the board is factory-finished or field-painted |
| Manufacturer track record | Decades of large-scale claims history in wet coastal markets | Shorter and smaller track record specifically in Pacific Northwest coastal conditions |
| Regional formulation | HZ5 line engineered for PNW moisture and freeze-thaw exposure | No dedicated PNW-specific formulation across the standard lineup |
None of this means a Cemplank warranty is worthless. It means that when we're the ones standing on the ladder and putting our labor behind a product, we want a warranty structure with a long, proven claims history in exactly the kind of weather Whatcom County throws at a house.
Installation Sensitivity: Why the Installer Matters as Much as the Board
Fiber cement siding, whichever brand, is unforgiving of shortcuts. Improper fastener placement, missing flashing details, wrong nail penetration depth, and tight joints without expansion gaps will cause problems regardless of manufacturer. James Hardie backs this up with a formal installer training and certification structure that we've built our crews around — specific fastener schedules, clearances, and flashing details published and enforced product-line by product-line. That gives us a documented standard to install to and to point back to if a warranty question ever comes up. Cemplank does not carry the same weight of contractor-facing installation infrastructure in this market, which means installation quality on a Cemplank job leans more heavily on whatever standards the individual crew happens to bring with them, with less manufacturer-level backup if something goes wrong.
Bellingham's Climate Puts Both Products to the Test
This part isn't theoretical for us — it's the reason the whole comparison matters here more than it would somewhere dry. Whatcom County homes deal with salt air rolling in off Bellingham Bay, driving rain that hits siding sideways for months at a stretch, and a moss season that runs long on north-facing walls and anything shaded by evergreens. Salt air accelerates finish breakdown on anything not properly cured and sealed. Driving rain finds every gap in flashing and caulking a siding job didn't get right. Moss holds moisture against the wall longer than most homeowners realize, and a board that doesn't shed water and resist that sustained dampness well is going to show it within a few years, not a few decades. A siding product's spec sheet numbers mean less here than how it actually behaves after a decade of this specific weather pattern, which is exactly why we weight manufacturer track record and regional engineering as heavily as we do.
Cost Factors to Weigh Beyond the Sticker Price
Material cost alone is a misleading way to compare these two products. The real cost comparison includes long-term maintenance, repainting cycles if the finish isn't factory-cured, and how easy it is to source matching replacement boards years later if a section gets damaged.
| Cost factor | What to consider |
|---|---|
| Upfront material | Cemplank often prices lower per square foot than James Hardie |
| Repainting cycle | Field-painted fiber cement typically needs repainting well before a factory-cured ColorPlus finish does |
| Color matching later | Factory finish systems with a documented, stable color program make future repairs easier to match |
| Warranty claim value | A warranty is only worth what the manufacturer actually honors — track record matters more than the stated term length |
| Resale perception | Buyers and inspectors increasingly recognize James Hardie by name, which can matter at resale |
A Practical Checklist for Comparing Fiber Cement Bids
If you're getting quotes and one contractor is proposing Cemplank while another is proposing James Hardie, here's what actually matters when you compare them line by line:
- Ask whether the board is factory-finished or will be field-painted on site
- Ask which climate-specific product line is being used for our region
- Get the warranty document itself, not just a verbal summary — read the transferability and proration terms
- Confirm the installer is manufacturer-certified for the specific product being installed
- Ask how fastener schedules and flashing details are being handled at seams, corners, and penetrations
- Ask how easy it will be to source matching replacement boards in ten or fifteen years
Why We Standardized on One Product
We didn't arrive at an all-Hardie policy because of a rebate or a dealer relationship — we arrived at it because we got tired of installation callbacks and warranty gray areas tied to inconsistent products, and because the one product that consistently held up in this specific coastal climate, with a warranty structure we trust and an installation standard we can train crews to and enforce, was James Hardie. Non-combustible, factory-finished, engineered by product line for Pacific Northwest moisture exposure, and backed by a warranty with a long claims history — that's what we're willing to put on a home and stand behind. If we can't say the same about a product, we don't install it, and that's the honest answer to why Cemplank isn't on our truck.
If you're weighing siding options for a home in Bellingham or elsewhere in Whatcom County, we're happy to walk through what's actually going on your walls and why. Reach out for a free, no-pressure estimate — no obligation, just a straight answer about what we'd recommend for your house.