Pittsburgh is a wet, changeable place to paint outdoors. The National Weather Service normals put the city at about 40 inches of precipitation and about 44 inches of snow a year. Exterior work has to be planned around dry spells.
What is the best time of year to paint the outside of a house in Pittsburgh?
The best months are late spring through early fall, roughly May to early October. Days are warm enough for paint to cure, and nights stay above the minimum temperature on the can.
Early fall is often the most reliable stretch, with mild days and lower humidity. Spring works well but brings more showers. Summer is fine if the painter works around afternoon storms and hot sun.
Can you paint outside when it is raining or about to rain?
No. Paint cannot go on a wet surface, and fresh paint needs dry hours before rain reaches it. We watch the forecast and stop early if showers are coming.
Prep work such as scraping can sometimes continue in damp weather under cover. Painting cannot.
It rained a few hours after painting. Is it ruined?
Usually not. If latex paint had a few hours to dry before the rain, it is normally fine. A light shower after that does little harm.
Heavy rain on paint that is still wet can wash it or leave streaks and spots. Those areas are let dry, then sanded lightly and recoated. Check the walls once they are dry.
How long after rain before siding can be painted?
Wait until the surface is dry all the way through. After it rains, smooth siding in sun and wind may be ready in a day. Bare wood, brick and stucco hold water longer and can need two or more dry days.
The same applies after power washing. A wall that looks dry can still be wet inside, and paint over damp wood blisters. Shaded north walls in our hollows and valleys dry slowest. A moisture meter takes out the guesswork.
How cold is too cold to paint outside?
Below the minimum on the label is too cold. For many exterior acrylics that is 50 degrees. Some are made to go on down to 35 degrees. The surface temperature counts, not just the air, and it must stay above the minimum for several hours after painting.
In Pittsburgh that rules out most of late fall, winter and early spring. A sunny 55 degree afternoon in November can be followed by a night near freezing, with dew on the wall by early evening. Paint that gets cold or wet before it cures can crack, stay soft or peel.
How hot is too hot, and is direct sun a problem?
Around 90 degrees and above is too hot for most paint, and direct sun is a problem even on milder days. Sun can heat siding far above the air temperature. Paint then dries before it levels and bonds, which leaves lap marks and blisters.
Painters follow the shade around the house: west and north sides in the morning, east side in the afternoon. Dark colors and metal siding heat up most.
Does humidity affect exterior painting here?
Yes. High humidity slows drying, and Pittsburgh summers are humid. Paint applied late in the day can still be wet when the evening dew settles on it.
That causes a dull, streaky or sticky film. The answer is to start after the morning dew has dried and stop early enough for the paint to set before evening.
Can you paint inside in winter with the windows closed?
Yes. Interior painting works well in winter. The heating keeps rooms warm and dry, so paint dries well, and low-odor paints make closed windows less of an issue.
A window opened a crack or a fan running helps the smell clear faster. Winter is a good season to book interior and cabinet work in Pittsburgh, because exterior work is on hold.
To plan an exterior job for the coming season, call or text (412) 668-1875.