You can paint the inside of a house during every season and under nearly every condition. The reason is that house interiors are controlled environments. Temperature and humidity can be adjusted so that they work best for painting. But painting house exteriors is an entirely different matter. You are at the mercy of the elements. Rather than adjusting conditions around your project, you need to adjust the project around conditions. When is the best time to paint the outside of your home?
The Best Season to Paint a House Exterior
Optimal painting season for house exteriors is usually thought of as summer. The weather is warm and the rain has tapered off. Summer does not mean the same thing in all parts of the country; it's more about the conditions than about what you call the season. For areas that experience hurricanes or monsoon-like conditions toward the end of the summer, try to start painting earlier in the summer. Extreme heat, too, prematurely cures paint; the paint practically dries as you are applying it. So, if you live in an area of extremely high temperatures, you'll want to avoid painting when the sun is directly shining on the painting surface.
Painting During Autumn
Fluctuations between temperature highs and lows is an important factor to consider when painting your house exterior. Paint does not dry well when temperatures during the day are 105 F and then suddenly drop down to 43 F in the evening and night. For that reason, early fall, when temperature extremes are mitigated, might be a good time of the year in your location to paint. Daytime and nighttime temperatures are often closer than during other times of the year.
In New York City, for example, average low temperatures are 47 F in October and 38 F in November. This makes mid-November the cut-off month for exterior painting season, at least based on averages. Yet the milder temperatures and relaxed fluctuations of October make this an ideal month for exterior painting in that area.
By contrast, in Columbia, South Carolina, you can push your painting season one more month later. Average lows in November are 45 F. It isn't until December that averages drop down to 39 F: cold but still within the range of premium paint specifications.
Painting During Winter
Paint manufacturers recommend a minimum outside temperature for painting. As paint quality has improved over the years, so too has the minimum temperature point. For a long time, it was recommended that you never paint a house when the ambient temperature is 50 F. Improved paint technology lets you push down as low as 35 F. In Northern states, stop around November. In Southern states, stop around December.
Painting in Moist Conditions
After a hard rain, wait at least one full day before painting. Check the surface to be painted. If it is wet, even in the slightest, do not paint. Even if it does not feel wet to the touch, it may be wet within, especially for porous surfaces like bare wood and masonry.
Moisture occurs indirectly, too. Dew forming overnight or in early evenings can quite easily ruin exterior paint–even though it was a dry, balmy 70 F just six hours earlier.
Homeowners may forget that paint is still drying after they stop painting for the day. Look at yesterday's evening low and today's predicted low. Even though lows tend not to occur until deep into the evening, it is prudent to assume that they might happen right after sunset.
Painting Seasons for Professional Painters
Some professional painters let almost nothing, not even inclement weather, prevent them from painting a house. While professional painters can be good at stretching seasons, it is just not possible to paint during all seasons.
In a cold, snowy Minnesota winter, you will not, or should not, find painters painting house exteriors; it is just too cold for the paint to cure. This is the season when professional painters switch gears and take on interior painting.
Professional painters in the Midwest often conservatively block off the entire period from mid-October to the end of March a period excluded from exterior painting. During the coldest of the cold months, even the low-temperature premium paints do not make a difference. A professional in mountainous areas of Eastern Massachusetts might even back off from exterior painting around the first part of October.