How temperature and humidity could affect your paint job

Painting is a big project that adds great visual appeal and value to your property. It takes a lot of time, money, and effort to paint a large surface, so you want to make sure it’s done right the first time to avoid having to re-start the project. Extreme temperatures and humidity levels are often unavoidable, but if you’re not careful in these conditions, you could have a botched paint job on your hands. Today, we’re going to discuss how temperature and humidity could affect your paint job and what you can do to combat these conditions so your project is finished smoothly and beautifully.

Can you paint in high humidity?

The first issue with painting in high humidity is that the bare surface may not dry completely before painting, leaving moisture between the wall and the new coat of paint. This can lead to mold growth, which will eventually grow through the new paint and require repainting. Working in high humidity is particularly difficult when painting wood. Moisture causes wood to swell, so when you paint it in overly humid conditions, you may start to see cracks in the paint coat as it dries.

After washing the surface, you’ll want to make sure you thoroughly dry it by running some oscillating fans in the room. To reduce the high levels of humidity, it’s a good idea to run a dehumidifier in the room for a day or two before painting to minimize these effects.

Red roller brush black paint on white wall
StockSnap/Pixabay

Can you paint in low humidity?

Is dry air better for painting? In some cases, it is, but painting in too low of humidity causes its own issues. When the air in a room lacks moisture, the wall’s material can over-absorb the paint and leave the surface looking porous or lightly speckled. This makes the overall color of the paint look drab or washed out. With some paint brands, dryness can also lead to cracking or peeling paint.

If the air in your working area is dry, consider running a humidifier a day or two prior, but be sure this doesn’t introduce too much moisture in the air and cause it to be too humid — that’s the opposite of what you want!

Can you paint in cold temperatures?

You may find yourself planning a painting project during cooler months. While it’s possible to successfully paint in colder conditions, it’s definitely not ideal and requires careful preparation. Cool air can cause issues with paint adhering to its surface, and it can also cause the paint to thicken. Thick paint takes longer to dry, and when paint stays wet for too long, it can easily begin to wrinkle, sag, or run. This leaves the coat of paint looking patchy and less smooth overall.

Some exterior paint brands and primers are more suited for painting in cooler weather, so read labels to find the best option. However, even these brands are not recommended for use in temperatures below 35 degrees Fahrenheit since the paint mixture could freeze and be unusable.

Since the sun will naturally warm any surface to a certain degree, it’s a good idea to paint along with the direction of the sun. Start where the sun will hit first and move in a westward direction as best you can. The sun will shine down on the applied paint and increase the temperature to an ideal one.

Can temperatures be too hot for painting?

You might think that painting in hot temperatures would be a good thing. The paint dries faster, so you can finish the job quicker, right? While heat does dry paint faster, you want to be sure the paint isn’t drying too fast. When the temperature is excessively hot, the very top layer of the paint dries quickly before the deeper layers have a chance to dry. This causes the coat of paint to begin bubbling up or blistering.

If you’re painting indoors and the space is too hot for ideal painting conditions, cool it down with some electric fans or an air conditioning unit. If your paint job is an exterior one, you’ll want to avoid having direct sunlight on freshly painted surfaces. It’s a good idea to paint the west and south-facing surfaces in the early hours of the day and then move on to the east and north-facing ones. This way, your paint will be in the shade for its premium drying hours.

Unfavorable weather conditions are unavoidable. If you have a painting project coming up, extreme temperatures and humidity don’t necessarily have to put a damper on your painting session. Before you put in all that time and effort into your new paint job, be sure you’ve prepared the space and your painting game plan for these conditions. If you’re prepared for the worst, you’ll be able to enjoy your beautifully upgraded surface and avoid having to start again from the beginning.

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