How do I prepare exterior wood siding for repainting when the old paint is peeling badly in NB?

Badly peeling exterior wood siding requires thorough and patient preparation — this is 80% of the entire job, and skipping or rushing any step guarantees the new paint will fail in 2-3 NB winters. Done correctly, a full exterior repaint with proper prep lasts 8-12 years on quality NB housing stock.

Start by identifying why the paint is peeling. On most New Brunswick homes — particularly older clapboard siding common in Moncton, Saint John, and Fredericton — peeling comes from moisture migrating outward from inside the wall, failed caulking letting water behind the siding, or paint applied over dirty, wet, or glossy surfaces. Fix the root cause first, or the new paint will peel for the same reason.

The preparation sequence is: wash, then scrape, then sand, then repair, then prime, then paint. Begin with a thorough pressure wash — 1,500-2,500 PSI is appropriate for wood siding. Let the siding dry completely — in New Brunswick’s spring and early summer, that can mean 3-5 dry days. Check wood moisture content with a moisture meter before you prime or paint — wood must be below 15%.

Once dry, scrape all loose and peeling paint back to a firm edge. Use a stiff-blade scraper on flat sections, a detail scraper around trim. You do NOT need to strip to bare wood everywhere — just remove everything loose. Feather the edges of remaining paint with 80-grit sandpaper.

Fill all nail holes and open joints with paintable exterior caulk, and re-caulk all seams — around window and door frames, at corners, and any gaps where siding meets trim. This step alone prevents most of the moisture infiltration that causes NB siding to peel.

Prime all bare wood and scraped areas. For cedar and spruce clapboard common in older NB homes, use an oil-based or high-adhesion acrylic primer — $40-60/gallon. Apply primer the same day bare wood is exposed — raw wood absorbs moisture quickly in NB’s climate.

For the topcoat, a 100% acrylic latex exterior paint at $55-80/gallon is the right choice. Two coats are mandatory.

A full exterior repaint on a bungalow in NB costs $4,000-7,000, while a two-storey runs $6,000-12,000. With badly peeling siding, expect the higher end. For any home where you suspect lead paint (pre-1978 builds), hire a professional.

---

Find a Painting Contractor

New Brunswick Painting helps you find local painting contractors through the New Brunswick Construction Network:

• Expressions Painting
• Loves Painting Ltd.
• Worry No More Handyman Services