Ideal Temperatures to Paint When It’s Cold
Some may consider painting outside in cold weather less than ideal. However, if temperatures are above 35 degrees, there is no risk of paint failure when using low-temp-specific exterior paints. Although the proverbial “Is it too cold to paint?” is a normal question during the cold weather season.
To validate a homeowner’s concern, product knowledge helps when painting in cooler weather. Otherwise, the paint could blister or peel. But that also stands true for heat and humidity.
The ideal temperature to paint is between 50 and 85 degrees Fahrenheit. So, temperatures below 55 are inevitably considered low-temperature applications and must be treated accordingly.
The Lowest Temperatures to Paint Outside
The best temperatures for oil-based paints range from 45 – 90 degrees. Surface temperatures must be 50 degrees Fahrenheit or above for most exterior latex paints. In contrast, a cold weather exterior paint such as Sherwin-Williams Latitude allows surface temperatures to be as low as 35 degrees.
Atmospheric temperatures differ from surface temperatures, while an outdoor temperature may be higher than surface temperatures in shady areas. Painting in hotter months, an experienced painter will dodge the sun and chase the shade, while during winter months, it is the opposite. Exterior painters are more successful in painting on the sunny side in late fall and early winter.
6 Steps to Painting in Cold Temperatures
There are additional considerations besides finding the sun when the temperatures are low, and you don’t need to be a painter to follow these basic steps.
- 1) Check the weather to ensure rain, high winds, or a cold front is not coming.
- 2) Check the surface temperature and look for visible moisture.
- 3) Heat the surface when needed using an outdoor heater.
- 4) Buy a low-temperature paint that allows cold-weather applications.
- 5) Purchase fast-drying caulking and paint supplies.
- 6) Allow plenty of drying time.
Cold Weather Painting Tips Based on Region
The possibility of painting outside in cold weather primarily depends on where you live. Northern US states have harsher winters, constituting a shorter painting season. Moderate temperatures with a clear forecast offer the longest times to paint outdoors.
If you live in Southern areas of the US, the most considerable setbacks from painting in the winter months are fewer working hours, primarily due to minimal daylight. But planning times for when the painting will begin and end are ideal no matter what challenge you face.
If you live in colder states and the weather is forecasted to have precipitation or change, use low-temperature paint and stop painting earlier to allow the paint to dry before being exposed.
To play it safe, start painting two hours later than usual and stop two hours earlier. Usually, by 10 AM, the temperatures and ground-level moisture have reduced. If it gets dark at 5 PM, stop painting at 3 PM. Or, if you are painting and the temperature is projected to drop, stop even earlier.
Allowing the paint to dry before reaching freezing temperatures will enable the paint to adhere to the surface. If paint freezes on the surface before it dries, it will not stick, resulting in cracking, blistering, and peeling.
Likewise, painting over wet surfaces will cause paint discoloration and loss of bond. The paint will lose bonding power in both cases and should be avoided to prevent premature paint failure and repaints.
Additional Tips For Painting When It’s Cold
Understanding exterior paint application temperatures is only one of many considerations. Caulk, painters’ putty, and primers are also affected by cold temperatures.
Painting over caulking that has not dried will cause cracks in paint coatings. We recommend high-performing quick dry caulking like Sherwin-Williams 1050A, which will dry faster in cooler conditions. Caulking not considered “quick dry” will require more time to cure before painting.
Another tip is to allow more time between paint coats. We recommend allowing 4 – 24 hrs. between coats at temperatures below 55 degrees. Even cold weather paints will need additional time – particularly dark colors will be most affected. Dark colors contain more colorant, inherently causing the paint to dry more slowly.
Cold Temperatures vs. Hot
Temperature, humidity, and surface moisture can all cause adverse effects to paint. Painting in high humidity can cause blistering and bubbles, while high temps can cause the same issue. There are also exterior paints available that will mitigate high-temperature paint failures. So, knowing which exterior paint to use during each season is crucial to paint performance.
Painting in the cold will increase paint cure time, but that is not exactly a drawback. Slower house paint dry times promote better adhesion, but all surfaces must be dry. So, why does colder weather take most of the shame? It’s because the general public has little understanding of how cold you can paint outdoors, and it’s a professional’s responsibility to educate them.
How Painting in the Cold Affects Cure Times
If temperatures drop below freezing for over 48 hours, there are no negative effects for low-temperature specific paints that have already dried. Once the surface reaches 50 degrees, the curing process will continue.
Some exterior painters refer to paint drying to the touch as “cure time,” which is inaccurate. Rather, paint cure time refers to the time it takes the surface to thoroughly harden. You can expect exterior paint to take longer to cure in colder weather, sometimes upwards of 30 – 45 days.
Slow paint cure times in cold conditions are even worse when using low-quality paint. We recommend using high-grade exterior paint to prevent doors and windows from sticking.
Additives That Allow Painting In Cold Conditions
Modern exterior house paints are formulated to be applied in various conditions while considering health and safety. House paints designed for colder weather applications contain additives that prevent paint solvents from freezing at low temperatures.
Ethylene glycol is a toxic additive once used in latex paint until the late ’80s when it was replaced with propylene glycol. Although some paint manufacturers still use ethylene. Propylene glycol renders less topical health concerns and is used in several household cleaners.
H2O is a solvent found in the majority of modern latex paints. Propylene glycol improves latex paint emulsion properties, allowing paint raw materials to mix, and it reduces water evaporation. Slower water evaporation slows down the time it takes paint to dry, allowing more opportunity to correct application mistakes.
Propylene glycol is the main ingredient for most exterior paints, allowing cold-temperature applications. It serves as an anti-freezing agent, allowing all water to evaporate before the acrylic and vinyl polymers are affected by cold temperatures. Paint solvents include water, glycols, blenders, and additional chemicals for making glycols and auxiliaries.
Conclusion
We all know that water freezes at 32 degrees, and painting below this temperature can cause issues. So, if the season doesn’t offer a proper climate, you must wait until the temperature warm-ups.
Timing is essential whether you are working through a cold season or planning and budgeting for the future. But if you are paying for a house painting service and the painter is using a low-temperature paint in conditions above 35 degrees and will warranty the service, there’s not much to be concerned about.
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