Winter, spring and fall: what stucco work can be done when in the GTA

The rule that sets everything

Manufacturers specify a minimum air and surface temperature for applying and curing base coats, adhesives and finishes, and it has to hold for a period after application, usually around 24 hours and longer in damp weather. In the GTA that rule is met reliably from late April to late October, with exceptions on either side. Below the minimum the coatings cure badly or not at all, and a finish applied in the cold can fail within a year. We do not apply finishes below the manufacturer's minimum, whatever the schedule says.

Spring

The busiest booking season. Walls that suffered over the winter show their blisters and cracks as the snow goes, and owners call. Early spring is for site visits, surveys and sealant work on dry days; by May the finishes start. Spring rain is the limit: coatings cannot go on a wet wall or be rained on before they set, so schedules move with the forecast. If you want work done in spring, book in winter.

Summer

The main season for new exteriors, resurfacing and recoats. Long days, warm nights and dry spells mean good curing. The one caution is heat: on a south or west wall in full July sun, finishes can dry too fast and show lap marks, so we work those elevations in the shade of the day or shade them. Summer is also when builders need us most, so new-construction slots fill early.

Fall

The second busy season and in some ways the best: cooler, usually dry, and walls are not baking. September and October are ideal for resurfacing, recoats and full exteriors. The limit is the first cold snap. Once overnight temperatures drop toward freezing, finish work stops, and anything not finished waits for spring or needs heat and hoarding. Fall is also the right time for a sealant check, before winter water gets in.

Winter

Finish coats and most base coat work stop. What can be done:

• Emergency repairs. A hole or an open blister is closed temporarily to keep water out, and the proper repair is scheduled for spring.
• Heated and hoarded work. On new construction and commercial jobs the wall can be enclosed and heated so coatings cure. It adds cost and is planned, not improvised.
• Interior stucco and some stone. Where the work is inside a heated enclosure.
• Site visits, surveys, quotes and planning. Winter is when the spring schedule is built. A visit in January gets you a spring date; a call in May gets you a summer one.
• Sealant, on mild days. Some sealants can go in at lower temperatures than finishes; we check the product and the forecast.

Timing by job

• Repairs: any warm month. Temporary weatherproofing any time.
• Sealant replacement: spring or fall, on dry days.
• Recoat or colour change: late spring to early fall, avoiding the hottest weeks on sun-facing walls.
• Resurfacing: May to October.
• New exterior or stucco over brick: May to October for the finish; preparation and brick repair can start earlier.
• Commercial and tenanted buildings: same limits, with phasing planned so no elevation is left half done when the cold arrives.

Weather during the job

Rain stops coating work for the day and sometimes the next. Wind on scaffold stops work for safety. Heat moves work to shaded elevations. We build a margin into every schedule and tell you when the forecast moves a date. A quoted duration is working days in reasonable weather, and we would rather lose a day than put a finish on a wall that is about to be rained on.

When to call

Earlier than you think. The best spring and fall slots go to people who booked a season ahead. If your wall needs work, a site visit in the off season costs nothing and gets you a date before the rush.