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Temperature To Paint Outside: Recommended Temperature For Exterior Painting

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A few years ago, we wrote a blog about when it’s too hot to paint outside. With the extreme heat we experience in Arizona, we can’t paint exteriors during the day for many months of the year.

Some customers think we don’t want to deal with the heat. While that’s true, it’s also because some paints just don’t dry and cure properly past a certain temperature.

This begs the question, what’s the best temperature to paint outside?

The Answer: Most paint brands recommend painting in temperatures between 35-90°F. The minimum temperature for most exterior paints used to be 50°F, but advances in waterborne technologies allow exterior paints to dry at temperatures as low as 35°F and as high as 90°F.

We’ll now spend the rest of this article explaining why paint brands and experts recommend this temperature range.

Understanding the Importance of Temperature

  • Adhesion: Paint needs to bond effectively with the surface it’s applied to. Low temperatures can cause paint to become too thick and viscous, making it hard to spread evenly. High temperatures bake paints, causing them to dry too fast. Both extremes will cause the paint to crack, peel, flake, and/or blister over time.
  • Drying Time: The temperature affects how quickly or slowly paint dries. If it dries too quickly, it can lead to an uneven finish. If it dries too slowly, it can attract dirt and debris, compromising the quality of the finish.
  • Performance: Extreme temperatures can alter the chemical composition of the paint, affecting its performance and longevity.

Ideal Temperature Ranges By Paint Type

Different types of paint have varying temperature requirements for optimal application and drying. Here’s a breakdown:

Latex Paint

Latex paint, also known as water-based paint, is popular for exterior projects due to its flexibility and ease of cleanup. The ideal temperature range for applying latex paint is between 50°F and 85°F (10°C and 29°C).

Here’s why:

  • Below 50°F (10°C): Latex paint can thicken and become difficult to apply. Additionally, it may not adhere well to the surface, leading to peeling and cracking.
  • Above 85°F (29°C): The paint can dry too quickly, causing brush marks, lap marks, and an uneven finish. High temperatures can also cause the paint to bubble or blister.

Oil-Based Paint

Oil-based paint is known for its durability and smooth finish. The ideal temperature range for applying oil-based paint is between 40°F and 90°F (4°C and 32°C).

  • Below 40°F (4°C): The paint becomes too viscous, making it challenging to spread evenly. It may also take much longer to dry, increasing the risk of imperfections.
  • Above 90°F (32°C): The paint may dry too quickly, leading to poor adhesion and a compromised finish. High temperatures can also cause the paint to wrinkle or sag.
    Acrylic Paint

Acrylic Paint

The ideal temperature for painting with acrylic paint typically falls within the range of 60°F to 75°F (15°C to 24°C). This range provides the best conditions for acrylic paint to adhere properly, dry evenly, and maintain its integrity. Here’s why this temperature range is ideal:

Humidity and Its Impact on Painting

Temperature is not the only factor to consider; humidity also plays a crucial role in the painting process. High humidity levels can slow down the drying process, while low humidity can cause the paint to dry too quickly. Here’s how humidity affects different types of paint:

  • Latex Paint: High humidity (above 70%) can extend the drying time, making it prone to drips and runs. Low humidity (below 40%) can cause the paint to dry too quickly, leading to an uneven finish.
  • Oil-Based Paint: High humidity can slow the drying process, but oil-based paint is generally more forgiving than latex paint in humid conditions. Low humidity can still cause issues with quick drying and uneven application.
  • Acrylic-Based Paint: High humidity levels can extend the drying time of acrylic paint, making it susceptible to sagging and runs. Acrylic paint performs best in moderate humidity, which allows for a controlled drying process and a smooth, professional finish.

Seasonal Considerations

The time of year you choose to paint can significantly impact the success of your project. Here’s a breakdown of the best seasons for exterior painting:

  • Spring: Spring is often considered an ideal time for exterior painting. Temperatures are generally mild, and humidity levels are moderate. Rain is rare in Arizona at this time, however, you should look out for it as it’s best to paint in dryer temperatures.
  • Summer: Summer can be a good time to paint but requires careful planning. Early mornings and late afternoons are the best times to paint to avoid the day’s peak heat. Be mindful of high temperatures and humidity levels, and always check the forecast for rain.
  • Fall: Fall offers similar advantages to spring, with mild temperatures and lower humidity. However, as temperatures can drop quickly, it’s crucial to ensure the paint has enough time to dry before colder weather sets in.
  • Winter: Winter is generally not recommended for exterior painting in most regions due to low temperatures and high humidity. The opposite is true in Arizona, we prefer to do exterior painting in the winter.

Best Paint For High Heat

If you’re reading this article, there’s a 50% chance you live in a high-heat area. If that’s true, many homes in your area are built with stucco. We recommend using elastomeric paint because it’s designed to protect masonry surfaces like stucco. Elastomeric paint contains more solids, allowing it to bridge small cracks and create waterproof barriers. 

Best Elastomeric Paint For Stucco:

Hillis Brothers Painting

If you’re in the Phoenix area, don’t hesitate to call Hillis Brothers Painting for your painting needs. Even in the dead of summer, we can take on exterior painting projects. However, during the summer, we do most of our work indoors.