Stucco Cure Windows at Altitude

Cement-based stucco needs to stay above 40°F for at least 48 hours after each coat, and it needs to stay damp enough to cure through — not dry out in an afternoon of sun and wind. Both are harder at altitude. The air is dry, the sun is strong, and the nights drop.

Grand Junction, 4,646 feet. Overnight lows clear 40°F by mid-April and hold until mid-October. The longest window in the territory, and exterior work that is frozen out everywhere else is going in here.

Glenwood, Montrose, Durango — 5,700 to 6,500 feet. Roughly May through September, with shoulder weeks either side that depend on the year. Watch the forecast, not the calendar.

Eagle and above — 6,600 feet and up. June through mid-September, honestly. Overnight lows at 6,600 feet dip below freezing well into May and again by early October. Vail, Aspen, Breckenridge, and Telluride are all higher still.

Tenting and heating the wall works, and it is what gets a mountain job finished in October. It costs money and it has to run all night, every night, for two days after each coat. Acrylic finish coats tolerate cold better than cement, which is one reason most commercial work here goes acrylic. And the base coat is the one that matters most — get it cured, and the finish has options.

They are watching the same overnight lows you are, and they know what the other crews in the valley are doing this week. Call before you schedule the crew, not after.