You can paint outside in San Bernardino in every month of the year. The climate is hot and dry in summer and mild in winter, with about 16 inches of rain a year, most of it between late fall and early spring. Heat, sun and wind cause more trouble for painters here than cold or rain.
What is the best time of year to paint the outside of a house here?
The best months are in spring and fall: roughly March through May and October through November. Days are warm, nights are mild and the walls are not too hot to hold paint. Winter is workable between storms. Summer is workable with early starts.
The numbers explain it. The average high is about 96 degrees in July and 97 in August, and about 68 in January. January nights average in the low 40s. Those are NOAA climate normals for the city.
How hot is too hot, and is direct sun a problem?
It is too hot when the wall itself is hot to the touch, and yes, direct sun is a real problem. A stucco wall in full summer sun is far hotter than the air. Paint put on a hot wall dries before it can level and bond. The results are lap marks, blisters and early peeling. Paint labels give a maximum surface temperature, and we follow it.
In summer the answer is to start early and follow the shade around the house: west walls in the morning, east walls in the afternoon. On the hottest days, outdoor painting should stop by early afternoon. The record high here is 118 degrees.
How cold is too cold to paint outside?
It is too cold when the air or the wall is below the minimum on the paint label. Many exterior acrylics list 50 degrees, and some are made for lower. San Bernardino days almost never stay that cold. The catch is winter mornings. Nights drop into the 40s and sometimes to frost, and walls are cold and wet with dew at sunrise.
In winter the painting day starts later, after the sun has dried the walls, and ends early enough for the paint to set before the evening chill.
Can you paint outside when it is raining or about to rain?
No. Paint needs a dry surface and enough dry time before rain hits it. Nobody should paint in the rain, on wet walls or when rain is due within hours. Covered areas, such as a porch ceiling under a deep roof, can sometimes continue.
Rain is easy to plan around here. Most of the year's rain falls from about November to March, with February the wettest month on average, and summer is nearly dry. Exterior days are moved around the forecast as needed.
It rained a few hours after painting. Is it ruined?
Usually not, if the paint had a few hours to dry before the rain started. Water-based exterior paint sets fast in our dry air. Once the rain has passed and the wall is dry, look for streaks, thin washed spots and a dull, blotchy look. Those areas need another coat. If rain hit paint that was still wet, that section has to be redone. A painter who checked the forecast should make that right.
How long after rain before siding or stucco can be painted?
Wait until the wall is dry all the way through, not just on the surface. After it rains, smooth wood siding in the sun may be dry the next day. Stucco and bare wood soak up water and need longer, often a day or two of dry weather, and shaded north walls take longest. The same wait applies after power washing. A moisture meter settles any doubt.
Do Santa Ana winds affect exterior painting?
Yes. Santa Ana winds are the local weather problem that people from other regions do not expect. In fall and winter, dry wind is funneled through the Cajon Pass and can gust very hard across the north end of the city, Rialto and Fontana. Wind blows dust and leaves into wet paint, dries the paint too fast and carries spray onto cars and neighbors' homes.
Spraying is out on windy days. The choices are brush and roller on sheltered sides, or another day.
Can you paint inside in winter with the windows closed?
Yes. Interior painting goes on all year, and winter is a good time for it. Water-based paints have low odor and dry well in a heated house with the windows closed. A fan and a cracked window speed things up. In winter here, most afternoons are mild enough to open the house for an hour or two anyway.
Planning an exterior job? Call or text (909) 487-2695 for a free estimate, and we will suggest the right weeks for it.