For interior and exterior painting projects, it’s important to know the temperature range in which you can successfully paint (or stain) your home, shed, or other exterior projects. If you start your project in temps outside this range, you risk premature paint failure and a tragic waste of time and money.
Generally, it is not recommended to apply paint when the temperature is less than 50 degrees.
However, you also need to take other variables into account. Paints, like materials, react to changes in temperature and humidity as well. In addition to a temperature that is too hot or too cold, excessive moisture in the air will cause the paint to not cure properly. The last thing you want to do is find yourself repainting your house because the conditions worked against you and the paint peels prematurely because it did not have time to cure.
Keep reading to learn the best temperature and humidity conditions to apply different types of paint …
What Temperature Is Best for Painting or Staining Outside?
For exterior paint projects, the best temperature range depends on the type of product you’re using:
- Latex Paint
Between 50-70 degrees F
- Oil-Based Paint
Between 45-90 degrees
If you must paint in lower temperatures, purchase the specially formulated latex paint made to perform in temperatures as low as 36 degrees F / 2.2 C. This paint contains coalescing agents that bolster paint curing attributes during low temperatures.
More Considerations to Keep in Mind for Exterior Painting
Since surface and air temperature can vary drastically, make sure to take this into consideration. Some exterior surfaces can take a day or two to warm up after a cold spell. Since some paints need at least a day to several days to fully cure, always check the weather after the day you paint to ensure the temperature doesn’t change too drastically while your paint or stain is drying.
To avoid painting in direct sunlight (which can dry the paint too fast) and on overheated surfaces outside, most experts recommend that you follow the sun’s shadow around the house. Allow time for the paint to dry to the touch before sunset, when cooler temperatures start, along with the formation of dew.
How the Temperature Affects Paint Finish Quality
Improperly cured surfaces also have a higher propensity for cracking, peeling, and chipping, which is why painting in the right temperature is so important.
If you paint your house when the temperature is too hot, the paint dries too rapidly and the heat compromises adhesion. At temperatures over 90 F / 32.2 C, bubbles and blisters form in the paint. Once the paint cures, it could start to peel away from the surface.
When the temperature drops below 55 F/ 12.7 C, it affects the speed at which the paint cures. When the paint takes longer to dry, the surface stays wet longer, attracting insects, dirt, grime, and other debris. Cold weather also reduces the overall life expectancy of the paint. Oil-based paints thicken in cold weather, causing stiffer brushing, heavier application, and less coverage per gallon.
How Humidity Affects Paint
Humidity refers to the measurement of water vapor in the air. Excessive humidity results in the formation of water vapor on the freshly painted surface. The ideal humidity level for exterior painting is between 40 and 70 percent.
Painting in a too-high humidity environment can result in:
- Leaching, when white or brown discoloration appears on the surface of latex or oil-based paints.
- Compromising the paint's protective qualities.
- Moisture evaporating too slowly from the solvents in the paint, which leads to longer cure time and a poor finish.
When painting a wood surface, you must consider humidity because the wood absorbs moisture from the surrounding air. This impedes adhesion of the paint to the surface and causes the paint to bubble and peel. One of the benefits of interior painting has to be the ability to control the climate. You can get rid of excessive humidity by running a dehumidifier or the air conditioner.
Reach Out for Professional Exterior Painting Services
Still, wondering what sets our painting services apart? Learn more about Five Star Painting’s exterior painting services and see for yourself. If you want our professionals to worry about the perfect weather window instead, give us a call at (888) 261-3633 or schedule a free estimate online.