What Is The Best Temperature To Paint Outside?

It’s important to consider the outside temperature and humidity before starting any exterior painting project. So what is the best temperature to paint outside in Idaho? Applying paint or stain to a project when it’s too cold may end up ruining your project entirely. Extreme heat can also be a detriment to drying paint. Because different temperature guidelines apply to different types of paint, it’s best to paint or stain when the temperature is between 60-85 degrees. In Idaho, this would mean that late Spring and early Fall are the best times to paint the outside of your home, deck, or patio furniture. 

What temperature can you paint outside? 

The last thing you want is to have to repaint your home because the outside conditions worked against you. For exterior projects, you never want to paint if the temperature is below 50 degrees or above 90 degrees Fahrenheit. Keep in mind that when using latex paint, it’s best if the temperature is between 50-70 degrees F. If you’re working with oil-based paint, between 45-90 degrees F. is your safe zone. However, you can purchase specially formulated latex paint made to perform in temperatures as low as 36 degrees if the job can’t wait for warmer days.

Painting in Extreme Heat 

The outside temperature is a huge factor when it comes to exterior painting. If it’s too hot or too cold, your paint might not bind together properly. This can also lead to other issues such as cracking and peeling of your paint once it fully dries. Painting when it’s too hot can also cause blisters and bubbles to form in the paint. With that said, we recommend not painting in temperatures above 90 degrees Fahrenheit. 

Painting in the Cold 

While no one would choose to paint outside in the cold, sometimes you just can’t avoid it. So, if you do attempt an outside painting project during the colder months in Idaho, be sure not to let the surface of the air temperature drop below 35 degrees for at least 36 hours after you’ve applied the paint. For best results, we recommend painting outside only if the temperature is above 50 degrees Fahrenheit. The cold air won’t allow your paint to cure properly. You may even end up with unsightly bumps or bubbles in your paint once the weather turns warm again.

Paint dries much slower in the cold. Be sure to allow ample time in between coats for your paint to completely dry. A good rule of thumb would be to wait a full 24 hours after each coat. 

The cold weather can even affect the quality of the application and the life expectancy of your paint. Cooler temperatures may cause the bristles on your paintbrush to stiffen, compromising the coverage and using more paint than is necessary. And because of the longer drying time, dirt, debris, leaves, and insects have more time to be attracted to and stick to your paint. 

Considering the amount of precious time and money you put into a painting project, it’s best to avoid working in cooler temperatures. The possible negative effects far outweigh the benefits. It certainly isn’t worth the risk.

How Humidity Affects Paint 

When it comes to exterior painting, warm, dry weather is ideal. Moisture can wreak havoc for painters. Too much humidity in the air can lead to water vapor forming on your newly painted surface. The best time to paint is when the humidity levels are between 40-and 70%. Fortunately, Boise has a high desert climate with an average humidity of 52.2%, making humidity less of a concern. Eastern Idaho and the northern part of the Gem state receive more precipitation than the Boise area by far. 

In the summer months that are hot and humid, it’s suggested that you start painting your home on the shady side and working your way around. This will help you as the painter avoid the heat of the sun as well as its constant glare. 

Below is a list of possible consequences for painting when the humidity levels are too high or too low. 

  1. Leaching- when high humidity causes brown or white discoloration on the surface of oil-based or latex paints. 
  2. Impedes adhesion- especially when working with wood surfaces, you must consider the humidity which is absorbed from the surrounding air. This causes the paint to bubble, peel, and keeps the paint from adhering properly to the surface. 
  3. Cracking– when the air doesn’t have enough humidity in it and is too dry, wood shrinks, leading to eventual splitting or cracking.

Painting in the Rain?

Obviously, it’s never a smart idea to paint when it’s raining outside. But one thing to be aware of is the need to allow plenty of time for the surface you will be painting to dry before applying any paint. We recommend giving the area you’ll be painting 4-8 hours of dry time before putting a brush to it. Once you’re finished painting, the area needs to remain dry for several hours. This will ensure a better bond and avoid problems down the road.

Best Exterior Paint 

Whatever paint you choose for the exterior of your home or shop is going to take a beating. Idaho summers can be sizzling hot in stark contrast to our wet and cold winters. That being said, it’s important you choose the best exterior paint that will protect your home and have excellent longevity. There are some real benefits to using water-based paints. These include being mold and mildew resistant, low VOC emissions, and superior adhesion. The fact that they can be used successfully even when the temperature falls below 50 degrees F. is also a win. With a short dry time, excellent coverage, and easy cleanup, water-based paints definitely have their advantages. 

However, latex paint has more flexibility, won’t yellow in the sun, and is more eco-friendly. Most painting professionals agree that latex paints are the superior choice for exterior jobs. Latex paint dries quickly, cleans up easily with just soap and water, and has less odor than oil-based paints.

Best Time to Paint Outside in Idaho Conclusion 

If you still have questions regarding exterior painting or need assistance with a painting project in the Boise area, don’t hesitate to contact Boise Home Painting. We offer a full range of painting services throughout the entire Treasure Valley. From Eagle and Nampa to Marsing, you won’t find a painting team more dedicated to doing the job right. Our professionals have years of experience and it shows. Click here to get your free estimate. We can help you with all of your commercial and residential painting needs!

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