Ferndale Exterior Board & Batten Siding for the Sumas Area: What Local Homes Are Up Against
Homes around Sumas sit close to the Whatcom County border country, where weather doesn't do anything halfway. Winters bring long stretches of driving rain pushed by wind off the Fraser Valley, summers are humid enough to keep moss and algae going nearly year-round on north- and west-facing walls, and salt-laden air drifting in from the Sound corrodes fasteners and finishes faster than most homeowners expect. Board and batten siding, with its bold vertical lines and wide flat boards, looks sharp on the farmhouse and craftsman-style homes common in this area — but that same wide-board profile is less forgiving of moisture mistakes than narrower lap siding. Get the water management wrong and you're not looking at a cosmetic issue, you're looking at rot behind the battens within a few seasons.
We're a Ferndale-based crew that already works homes in and around the Sumas area, so we're not guessing at what this climate does to a wall system. We've built our board and batten process around what actually survives it.
What Board & Batten Siding Actually Is
Board and batten is a two-layer siding pattern: wide vertical boards installed with a gap between them, then narrower strips (the battens) fastened over each seam to cover the joint. Done right, it reads as one of the cleanest, most architecturally distinct siding styles available — it's a common choice for farmhouse, modern farmhouse, and craftsman exteriors, and it pairs well as an accent alongside lap siding on gables, dormers, and entry features.
Why It Behaves Differently Than Lap Siding
Lap siding sheds water by overlap, board over board, course after course. Board and batten instead relies on the batten covering the seam and on a drainage gap behind the whole assembly to move any water that gets past the surface back out and down. That means the water management is happening mostly out of sight, in the gap between the siding and the wall, rather than in the visible overlap. If that drainage layer isn't built correctly, board and batten will trap moisture instead of shedding it — which is exactly the failure mode this region's rainfall volume is good at finding.
Why James Hardie Fiber Cement Is the Right Material Here
We install James Hardie fiber cement siding exclusively — we don't run vinyl, LP SmartSide, primed wood, cedar, or other fiber cement brands. For a wide-format product like board and batten, that standard matters more than usual, because wide boards move more with temperature and moisture swings than narrow ones, and that movement is where inferior materials show their weaknesses first.
Built for This Climate Specifically
Hardie's HZ5 product line is engineered for the Pacific Northwest's freeze-thaw cycles and sustained moisture exposure, with a moisture and mold resistance profile that holds up to the kind of prolonged wet weather Whatcom County sees for months at a stretch. Fiber cement doesn't swell, cup, or delaminate the way wood-based products can when they take on repeated moisture, and it won't support the kind of pest activity that softened wood trim invites.
ColorPlus Finish vs. Field-Applied Paint
Board and batten's large flat faces show every flaw in a paint job — uneven sheen, lap marks, early fade — more visibly than a shadow-lined lap profile does. Hardie's ColorPlus finish is baked on at the factory under controlled conditions, with UV-cured coats that resist the chalking and fade that salt air and constant damp accelerate on field-applied paint. It also carries a stronger, factory-backed warranty on the finish itself, not just the substrate.
What a Correct Board & Batten Installation Involves
Drainage Plane and Rainscreen Gap
Every wide-board installation we do starts with a proper weather-resistive barrier and a furring or rainscreen gap behind the siding. That gap is what lets bulk water that gets past the batten joints drain down and evaporate instead of sitting against the sheathing. Skipping this step is the single most common shortcut that turns board and batten into a rot problem, and it's invisible once the siding is up — which is exactly why it has to be right the first time.
Fastening Pattern
Boards and battens each need to be fastened independently into framing, following Hardie's specified fastener spacing and edge clearance — not just nailed through both layers together. Blind or improperly spaced fastening is a common cause of boards working loose or battens cupping away from the wall over a few winters of freeze-thaw movement.
Flashing and Joint Detailing
Every horizontal transition — window and door heads, under trim boards, at the foundation line — needs flashing that directs water out and away from the wall, not just caulk covering a gap. Caulk is a maintenance item that fails eventually; flashing is permanent. We treat caulk as the last line of defense, not the water management plan.
Gapping and Expansion
Fiber cement boards need a specified gap where they meet trim, corners, and each other to allow for expansion. Battens installed too tight, with no room to move, are one of the more common causes of cracking and bowing we get called out to fix.
Common Mistakes We See on Board & Batten Jobs
- No rainscreen gap — siding fastened directly to the weather barrier with no drainage path
- Battens face-nailed through both layers instead of each board fastened independently
- Caulk used to "solve" a flashing detail instead of actual flashing
- Boards butted tight against trim and corners with no expansion gap
- Mixed materials (wood trim with fiber cement field, or vice versa) with no plan for how each moves and weathers differently
Our Process for a Sumas-Area Board & Batten Project
- On-site assessment — we look at existing siding condition, sheathing, and any signs of past moisture intrusion before quoting anything
- Wall prep — repair or replace any compromised sheathing, install a code-compliant weather-resistive barrier
- Rainscreen and flashing installation — furring strips, window and door head flashing, and all transition details, before a single board goes up
- Board and batten installation — Hardie boards and battens fastened to spec, with correct gapping throughout
- Finish and detail work — trim, corners, and caulking at the specified maintenance joints only
- Walkthrough — we go over what was done and what to expect from the finish over time
Cost Factors for Board & Batten Siding
| Factor | Why It Matters |
|---|---|
| Existing sheathing condition | Rotted or damaged sheathing found during tear-off adds repair cost before new siding goes on |
| Wall complexity | Gables, dormers, and multiple wall planes take more cutting and detail work than flat wall runs |
| Batten spacing and width | Narrower, more frequent battens take more labor than wide-spaced patterns |
| Trim and corner detailing | Board and batten shows trim lines more prominently than lap siding, so corner and window trim choices affect both cost and final look |
| ColorPlus color selection | Factory-applied finish is priced into the board itself and varies by color line |
| Access and site conditions | Two-story walls, tight lot lines, or limited staging area affect labor time |
Maintaining Board & Batten Siding in This Climate
- Rinse siding annually to clear moss, algae, and salt residue before it builds up on north- and west-facing walls
- Inspect caulk joints at trim and penetrations each year — recaulk before a joint fails, not after water gets behind it
- Keep gutters and downspouts clear so roof runoff isn't dumping directly onto a wall section
- Trim back vegetation and landscaping that holds moisture against the siding
- Watch for any soft spots, staining, or bowing at board and batten seams, and have them looked at early
Why Hiring a Crew That Already Works the Sumas Area Matters
Board and batten's drainage plane, fastening pattern, and flashing details are all things a homeowner can't inspect after the siding is up — you're trusting the install crew got it right the first time. A crew that already works homes in the Sumas area has seen how this specific climate treats a wall system over multiple winters, not just what a spec sheet says should work. We build every board and batten job around Whatcom County's rainfall and moss exposure, using James Hardie fiber cement because it's the material we trust to hold up to it, and we stand behind the installation, not just the product.
If you're weighing board and batten siding for a home in the Sumas area, we're happy to walk the property, look at what's there now, and put together a straightforward, no-pressure estimate — just fill out the form below.