The outdoor season is the scarce resource
Exterior paint and stain only work when the surface and the air are warm enough for the product to form a film, and stay that way long enough for it to cure. Every can lists a minimum application temperature on its label, and many list a minimum for the overnight low as well, not just the afternoon high. In Grand Forks, the figures below show why that line on the label matters more than the brand name.
What NOAA's normals count
NOAA's U.S. climate normals for Grand Forks International Airport count about 184.7 days a year with a low of 32°F or below. The same normals count about 101.3 days a year when the high at Grand Forks International Airport stays at or below 32°F.
Those two numbers describe two different limits. A day when the high never gets above freezing is a day no exterior coating goes on. A night that drops to freezing after a mild afternoon is subtler: the paint may feel dry to the touch by evening, but a film that hasn't finished curing can be harmed by cold, dew or frost settling on it overnight.
Summer has its own limit
The figures for muggy weather come from a different station, the one NOAA names Grand Forks Air Force Base. In an average year at Grand Forks Air Force Base, NOAA counts about 79 hours with the wet-bulb temperature above 73°F and about 409 hours above 67°F.
Wet-bulb hours measure damp, heavy air. Paint dries by giving up water or solvent to the air around it, and damp air takes it more slowly. On a sticky afternoon a coat can stay soft longer than the label's dry time suggests, and dew forming in the evening can leave a fresh latex coat streaked or dull. Ask your painter how they decide whether a humid day is a painting day, and how late in the afternoon they stop applying exterior coats.
How a crew fits the work into the window
Because the exterior window is short, the order of work matters:
- Prep early, finish in the steady weeks. Washing, scraping, sanding and caulking can start as soon as the siding is dry and thawed. The finish coats belong in the stretch when both days and nights stay above the label minimum.
- Follow the sun around the house. Many crews avoid painting a wall that's still cold and damp from the night, or one that's baking in direct afternoon sun.
- Prime bare wood the same season. Bare wood left unprimed over a winter weathers and takes on water, and may need sanding again in spring.
- Agree on weather days in writing. Ask what happens if a cold snap or rain arrives halfway through: does the crew stop, and does the price change?
The cold months are interior months
The long run of freezing days doesn't stop painting; it moves it indoors. Rooms, ceilings, trim, doors and kitchen cabinets can be done in winter as long as the house is heated and the crew can ventilate safely. A painter will want the room kept warm, and steady, for the full recoat time on the label. If you'd like the interior done as well as the outside, booking the inside work for the cold months can leave the warm weeks free for the exterior.
The state contractor law, as the statute reads
The North Dakota Century Code is the source for the state rule on this page: North Dakota law requires a contractor license from the Secretary of State when the cost, value, or price per job exceeds $4,000; the definition covers repair and alteration of buildings and does not name painting. We don't read more into it than that, and the statute itself is linked in the fact card on this page.
Before you sign
Ask for a written proposal that names each surface, the preparation, the primer, the number of coats and the products, and the lowest overnight temperature those products allow. Our pricing guide explains what moves the price, and the guide to paint sheens and finishes helps you choose how glossy each surface should be.