When Is It Too Hot To Paint Outside

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No one likes to paint in the heat, and if you have been outside painting on a hot day, you know it is not fun or easy. Even worse, did you know the heat does not only affect the painter but the paint too? In fact, painting when it is too hot can ruin your paint job.

That doesn’t mean that you can’t paint when it is hot, but there is a limit to the temperature you should paint at.

We will take you through how to get the best paint finish when heat is a factor.

Is It Ever Too Hot To Paint?


The heat changes the way paint dries, and although there are paints than handle the heat (and cold) better, we prefer to cover all our bases and never paint when it is above 85 F. It is also good practice to not paint when the temperature is below 50 F. 

There are exceptions to this rule, but painting between 50-85 F will get you the best results.

What Paint Does Better In High Heat?

If you are painting in high-heat conditions, you are probably painting outdoors, and when that is the case, you will be using oil or latex paint. Both deal well with high temperatures, and both will work well within the 50-85 F range we gave above.

We recommend choosing oil paint over latex if you are painting in high heat. If you do, you can go a little bit higher than the given range (up to 90 F),  and you can also go lower (down to 40 F).

You also get what you pay for. While oil and latex paint both deal well with the heat, cheap paint might not be good enough to cope with the upper end of the range. Always use high-quality paint to get the best finish and save you money in the long run.

What Precautions Should I Take When It Is Hot?

The best tip we can give when it is hot outside and you need to paint is to protect the painter. If you are going to be outside for a long time, be sure to cover your skin with breathable clothing, always wear a hat, and drink lots of water. Outside of that, you can follow these tips:

  • Stay out of the sun. Try to paint areas in the order the sun has touched them. Not only will this ensure that any moisture is removed from the painting area, but the sun will not dry the area too quickly. In high heat, quick-drying will result in a gummy finish as the water content dries far quicker than the solvents.
  • You can thin your paint by adding 10% more water content. Do this in small batches. The extra water content in the paint will help even the drying time when it is hot out.
  • If you are painting from a tray, add some ice cubes under the liner. When you pour the paint into the tray, it will start evaporating with the heat, and the water content will evaporate first. The ice will reduce the evaporation time.

What Happens If You Paint In The Sun Without Precautions?

We recommend not painting in high heat at all, and that way, you won’t have to deal with any potential problems. If the heat is creeping up, and you follow our tips above, you shouldn’t have any problems. But, if it is far too hot or you don’t prep properly, you will run into many problems.

When the water content and solvents don’t dry at the same rate, you are left with only the solvents, resulting in a gummy material that will not dry evenly. You also have a situation where you cannot apply the paint evenly, and there will be brush strokes visible in the finish. And, as an uneven coat of paint dries, it will start peeling, cracking, or chipping.

Thankfully, these problems are easily avoided. Simply paint when it is not hot, and if you have to paint when it is hot, take the right precautions and prep properly.

How Does Heat Affect Paint Over Time?

The heat will affect the paint when applied, but hot weather and direct sunlight will also degrade the paint over time. If you have followed the tips above to apply paint to your exterior walls without it drying unevenly or evaporating too rapidly, you might still have to be mindful of the heat year-round.

If you live in a hot climate, you can protect furniture and other smaller items by covering them when the sun is out. You can also protect walls with canopies and lean-tos, but this is not always possible.

If you are painting a wall that is not covered, you have two options. The first is to choose high-quality paint that will last a long time. You might spend more, but it is going to be worth it. Your second option is to recognize that you will have to paint more frequently. Paint is not going to last as long in high temperatures.

Final Thoughts

There are some precautions that you can take to ensure a high-quality finish when you are painting exterior walls in high heat. And high-quality paint is the way to go.

But, we just want to reiterate that you should always protect the painter and the paint. Plan your day when you are painting outside and get up early so you can start painting when the UV levels are low. You can also split your time between the morning and the evening. Follow the sun around your building, so you are always painting in the shade. And, when watering your paint down, don’t forget to drink water too. Wear a hat and sunglasses always, and don’t forget to take a break if the heat affects you.