Bellingham Exterior One Product, One Standard
We get asked about this a lot: why does a contractor working all over Whatcom County only install one brand of siding? It's a fair question, and the honest answer is that we'd rather be excellent at one system than mediocre across five. James Hardie fiber cement is what we've standardized on, and this page explains the reasoning without the sales pitch.
What Bellingham Siding Actually Deals With
Siding in Bellingham isn't fighting a generic climate. It's fighting salt-tinged marine air off Bellingham Bay, long stretches of driving rain that come sideways off the Strait, and a moss and mildew season that can run eight or nine months out of the year in shaded, north-facing lots common in neighborhoods around Whatcom County. Any siding product you put on a house here needs to handle sustained moisture exposure, resist organic growth, and hold its finish without chalking or fading under UV that, while not intense, is persistent for months at a time.
Wood-based products swell, check, and rot when moisture gets behind or into them. Vinyl can warp and fade, and its seams and channels give algae and moss plenty of places to take hold. We're not saying every one of those products fails — we're saying that in this specific climate, the margin for error is thinner than it is in drier parts of the country, and fiber cement gives us more of that margin.
Why Fiber Cement, Specifically Hardie
Fiber cement is a mix of cement, sand, and cellulose fibers, engineered to be dimensionally stable — it doesn't expand and contract with moisture the way wood does, and it doesn't get brittle and crack the way some vinyl does in cold snaps. James Hardie has been manufacturing it longer than most competitors have existed, and their manufacturing consistency is what lets us install with predictable results job after job.
The HZ5 Climate Engineering
James Hardie makes region-specific formulations, and Western Washington falls into their HZ5 zone — engineered for areas with significant moisture exposure and freeze-thaw cycling. That's not marketing language; it affects the actual composition of the board. It's one of the reasons we don't substitute a generic fiber cement product: Hardie is the only major manufacturer that engineers to this level of regional specificity, and Bellingham's climate is exactly the kind of environment that formulation is built for.
ColorPlus Factory Finish
Most siding failures we see aren't the substrate failing — they're the paint failing, letting moisture behind the finish where it can't dry out. Hardie's ColorPlus finish is baked on in a controlled factory environment, multiple coats, cured before the board ever reaches a job site. That gives a more even, UV-resistant finish than field-applied paint, and it comes with its own finish warranty separate from the substrate warranty. For a region with our moss and algae pressure, a finish that resists staining and holds color longer means fewer repaints over the life of the siding.
The Warranty Structure
James Hardie backs their products with a strong transferable limited warranty on the siding itself, plus a separate warranty on ColorPlus finishes. Transferability matters for resale — a new owner isn't stuck taking your word for the siding's condition. We only install products where we can stand behind both the material and our workmanship without a warranty full of exclusions for the exact climate conditions we work in every day.
Why We Don't Install Everything Else
We've looked at LP SmartSide, vinyl, other fiber cement brands like Cemplank and Allura, and traditional primed spruce or cedar. Each has a place in the market and each has homeowners who are happy with it. Our decision to not install them comes down to a few practical things: inconsistent regional engineering, finish systems that rely more heavily on field application and maintenance, warranty terms that are harder to stand fully behind, and — frankly — the value of our crews becoming true specialists in one installation system rather than generalists across several. Hardie's installation requirements around flashing, clearances, fastener patterns, and joint treatment are specific, and doing them right, every time, is easier when it's the only system your crew touches.
What Correct Installation Looks Like
- Proper rainscreen or drainage plane behind the siding, critical in a region with our rainfall totals
- Correct fastener type and placement per Hardie's published specs, not generic nailing patterns
- Minimum clearances from grade, roof lines, and decks to keep moisture from wicking into board edges
- Factory-cut and factory-primed edges wherever possible, with field-cut edges properly sealed
- Attention to caulking and joint treatment that won't trap moisture against the board
A great product installed poorly will still fail. That's part of why we limit ourselves to one system — it lets us guarantee not just the material, but the process behind every board we hang on a home in Bellingham or elsewhere in Whatcom County.
If you're weighing siding options for an upcoming project, we're happy to walk your home, talk through what Hardie's product lines and colors would look like on your house, and give you a straightforward, no-pressure estimate.