Paint keeps peeling off my New Brunswick cottage's south wall, what now?

Peeling paint on a south-facing wall is almost always a moisture problem, not a paint problem — and in New Brunswick's climate, there are a few very specific culprits worth investigating before you reach for a brush.

The south wall gets the most sun exposure, which means it goes through the most dramatic daily temperature swings. That constant expansion and contraction breaks the paint film's bond with the substrate. But the bigger issue is usually what's happening behind the wall. If your cottage has little or no insulation (very common in older NB camps), warm interior air hits the cold wall sheathing, condenses, and that moisture migrates outward — lifting paint from the inside out. You'll often notice the peeling starts at the bottom of boards or around window and door trim, which are the paths of least resistance for escaping moisture.

Start with a hands-on inspection before doing anything else. Press on the siding boards — any softness, sponginess, or give suggests rot has started. Check the bottom plate and any exposed framing around windows. Probe with a screwdriver; if it sinks in easily, you've got rot to address before repainting. Also look at your caulking around windows and trim — NB's freeze-thaw cycles (we regularly see 30+ freeze-thaw events per winter in many areas) destroy caulking fast, and even a hairline gap lets in enough water to cause significant peeling.

For a camp or cottage specifically, consider whether the building is heated year-round or sits cold all winter. Unheated camps are actually less prone to interior moisture drive, so if yours sits vacant from October to May, the peeling is more likely from exterior water intrusion — failed caulk, end-grain exposure on boards, or a roof drip line hitting the wall. If you've recently converted it to four-season use or added insulation without a proper vapour barrier, that changes the equation significantly and interior moisture drive becomes the prime suspect.

Once you've addressed the root cause, the fix itself is straightforward: scrape all loose paint back to a firm edge (a good carbide scraper is your best friend here), sand the feathered edges smooth, spot-prime any bare wood with an oil-based primer (oil primer penetrates and seals end grain far better than latex on weathered wood), then topcoat with a quality 100% acrylic exterior latex. For south walls in NB's climate, a satin or semi-gloss finish holds up better than flat — it sheds water more effectively. Expect to spend $80–$150 on materials for a typical cottage wall if you're doing it yourself.

Timing matters a lot in New Brunswick. Your painting window is genuinely narrow — May through September is ideal, and even then you want surface temperatures above 10°C and no rain forecast for 48 hours. Don't paint in direct hot sun on a south wall; the paint skins over before it can bond properly. Early morning or overcast days are your friend.

If the rot or moisture damage is significant, or if you're unsure whether you have a vapour barrier situation to sort out, that's worth a conversation with a local contractor before you invest in paint. A professional can also assess whether the siding itself needs replacing — LP SmartSide or fibre cement products like HardiePlank hold up extremely well on south-facing NB walls and essentially eliminate the repainting cycle.

Browse contractors in our directory at New Brunswick Construction Network to find painters and siding specialists in your area.