Exterior paint: the first maintenance step for a heritage home

On a heritage home, exterior paint isn't decoration; it's the first barrier against water. When the film breaks, wood absorbs moisture, frost cracks it open, masonry fissures, and what would have been a $4,000 project turns into a $25,000 bill. For the work itself, a painter used to older homes makes the difference: see painters in Montreal or painters in Quebec City. Repainting isn't a cosmetic choice. It's the most cost-effective maintenance you can do on this kind of building.

When it's time to repaint: the signals to read

A good exterior paint job lasts 8 to 12 years in Quebec, sometimes 15 on north-facing or shaded walls. End of life doesn't show up all at once; it reads in a series of small clues:

• Crackling in a fine grid pattern on flat surfaces: the paint is breaking down like bad glaze. Stage one.
• Fading and loss of sheen on south and west elevations, exposed to sun.
• Blisters under the paint, especially on lower boards: water is migrating behind the film.
• Active flaking: this is last call. The wood underneath is already taking damage.

A simple test: press clear packing tape onto a suspicious area, pull it off in one motion. If chunks of paint come with it, it's time. If nothing lifts, you can buy another season.

The acrylic-over-oil trap

This is the most expensive mistake a heritage homeowner can make: applying modern acrylic paint directly over old oil-based layers. Oil has penetrating power that lets wood breathe. Acrylic forms a sealed film on top. Result: moisture from the wood gets trapped under the new film, and the paint starts peeling in large sheets within 2 or 3 years, sometimes less.

Before 1980, almost all exterior wood on Quebec homes was painted with oil. Many still are. To check: scrape a discreet area down to the substrate. If the deep layers are yellowed, glossy, glass-hard, it's oil. If they're matte and rubbery, it's acrylic.

With an oil base, you have two options: strip down to bare wood (long and expensive, but the only true reset), or use a specific bonding primer (e.g. Zinsser Cover Stain or XIM Peel Bond) that bridges old oil and new acrylic. Without that bridge, you'll repaint every 3 years.

Prep: where 80% of the finish's life is decided

The golden rule among heritage painters: 80% of the time goes into prep. The topcoat only lasts if everything underneath is sound.

Non-negotiable steps:

1. Soft pressure wash (≤ 1,500 PSI, no more) with a mild detergent to remove pollution, pollen, dust. Higher pressure pulls nails and saturates wood.
2. Scraping and sanding of loose paint. Never sand pre-1980 paint without a P100 mask; almost all of it has lead.
3. Wood rot repair with epoxy (Abatron LiquidWood + WoodEpox) or grafts. Any soft area must be treated before painting.
4. Caulking of joints around windows, doors, wall returns. A single open joint can reintroduce water exactly where it had no access yesterday.
5. Primer on all bare wood, within 24 hours so it doesn't grey out.

A serious crew spends 3 to 5 days on prep alone for an average duplex. Crews that do it in a day and apply the finish the next morning are precisely the ones causing the acrylic-over-oil failure.

Choosing the paint and the colors

Four paint families make sense on a heritage home:

• Alkyd oil paint: the most traditional, still sold by Benjamin Moore (IronClad line) or Sherwin-Williams. Excellent on old wood because it penetrates. Lasts 12 to 15 years, but dries slowly (24 to 48 hours between coats) and emits more VOCs.
• High-quality 100% acrylic (Aura, Regal Select, Duration): excellent over a proper bonding primer. Lasts 8 to 12 years. Dries in 4 hours.
• Water-based alkyd: a useful compromise, low odor, oil-like behavior. Lasts 10 to 12 years.
• Lime or silicate paint: for painted masonry surfaces (rare in Quebec but useful on certain limestone). Breathes, doesn't form a film, lasts 15 to 20 years.

On color, traditional Quebec schemes rarely used more than 3 or 4 tones: a body color (wall or siding), a trim color (frames, cornice), an accent color (door, shutters), and sometimes gilding for ornamental details. English green, burgundy, burnt ochre, off-white, chocolate brown are the classics. Avoid bright modern colors: they date the work in five years.

If your home is in a heritage-value district (Old Montreal, Old Quebec, parts of the Plateau), a permit and CCU review may be required for any street-visible color change. Check before you buy paint.

Frequently Asked Questions

How often should a heritage home be repainted?

Every 8 to 12 years for exterior wood, sometimes 15 on shaded sides. South and west elevations, more exposed to sun and weather, often need a mid-life touch-up (wash and spot-repair) at the halfway mark.

How much does a full exterior repaint cost in Quebec?

For a typical Montreal duplex with proper prep: between $12,000 and $22,000, prep and paint included. The price depends mostly on starting condition. A home that hasn't been repainted in 20 years can run $35,000 or more because the prep becomes massive.

Can I do this myself?

Yes for one-story facades with little ornament, if you have the time (figure 2 to 3 weeks of weekends), the equipment (scaffolding, sanders, P100 mask), and the patience. No for anything above 8 feet, for homes with carved gingerbread trim, or if you suspect lead paint. The gap between an amateur and a pro shows up in five years.

When's the best time to repaint in Quebec?

Mid-May through late September, with the ideal window in June and late August when humidity is lower. Paint should never be applied below 10 °C or under threat of imminent rain. Many serious heritage crews are booked a year out; you start shopping in fall for the following summer.