The Best Exterior Paints to Keep Your Home Cooler in Hot Climates
For homeowners in hot climates, keeping the exterior of your home cool can be a constant battle. The intense sunlight and high temperatures can cause exterior paints to fade, peel and deteriorate rapidly. This results in exterior walls absorbing more heat from sunlight, leading to higher cooling costs and uncomfortable indoor temperatures.
To maximize exterior paint performance in hot weather, it's crucial to choose paints designed specifically to reflect sunlight and resist deterioration.
What Makes a Paint "Cool" for Hot Weather?
When searching for exterior paints to keep your home cool, there are a few key properties that make a paint effective for reflecting heat:
Solar Reflectance
Solar reflectance refers to a surface's ability to reflect sunlight and infrared heat rather than absorb it. For exterior house paints, you want a high solar reflectance index (SRI) of 78 or above. The higher the SRI, the greater capability the paint has to reflect heat.
Paints with solar reflective pigments are designed to reflect much of the sun's UV and infrared rays. This significantly reduces heat transfer through the exterior walls into the home. High SRI paints can lower wall surface temperatures by up to 50-60degF versus traditional darker paints.
Special Pigments
Solar reflective exterior paints contain special pigments that give them enhanced reflective properties. These pigments are designed to reflect the majority of sunlight across infrared and ultraviolet wavelengths.
Some paint manufacturers have created their own solar reflective pigments. For example, Sherwin-Williams uses ceramic pigment technology in their Duration Heat Reflective Collection. Others enhance titanium dioxide and other pigments to boost reflectivity.
Thermal Emittance
Thermal emittance is another important property related to exterior paint surface temperature. Thermal emittance refers to how easily the painted surface can radiate absorbed heat. The combination of solar reflectance and thermal emittance determines the overall temperature of the painted exterior surface.
Paints that have both high reflectance and high emittance will stay cooler in direct sunlight. Look for solar reflective exterior paints that also provide a high thermal emittance over 0.85.
Features to Look for in Exterior Paints for Hot Climates
When researching and evaluating exterior paint options for hot weather, there are several important features and properties to consider:
Solar Reflectance Index
As mentioned earlier, look for paints with a solar reflectance index (SRI) of at least 78, and ideally as high as possible. The higher the SRI, the greater the paint's ability to reflect solar radiation and minimize heat transfer through the painted surface.
Many brands list the specific SRI values for each paint color they offer. Lighter colors tend to have higher SRI levels than darker hues.
UV Resistance
Since UV rays from sunlight are intensely strong in hot climates, it's crucial to pick an exterior paint fortified with UV absorbers and inhibitors. UV-resistant paints will better retain their solar reflectance, resisting fading, degradation and erosion from sun exposure over time.
Breathability
Exterior paint breathability allows for moisture vapor to pass through the paint film without blistering or causing adhesion issues. This "vapor permeability" is essential for proper performance, especially in humid climates where moisture can get trapped.
Acrylic latex paints are inherently breathable. Look for paints specially formulated to optimize breathability and moisture control.
Binders: Acrylic vs. Elastomeric
Most residential exterior paints have either an acrylic or elastomeric binder. Acrylics offer good overall performance at an affordable price point. They expand and contract well as temperatures fluctuate.
Elastomeric paints provide maximum flexibility and longevity, making them ideal for regions with extreme temperature swings. However, they are significantly more expensive than acrylics.
In general, acrylic latex paints are sufficient for many hot climate situations. Use elastomeric paints if your local temperature range is more severe or your home experiences a lot of expansion/contraction.
Primer
Priming before applying exterior paint is always recommended for improved adhesion and durability. Some exterior paints come with a primer built in, while others require a separate primer coat.
Primers with solar reflective pigments offer an ideal solution to further reduce thermal heat gain through exterior walls in hot climates.
Proper Surface Prep and Application
No matter what exterior paint you choose, proper prep work and application is crucial to get the best and longest-lasting results:
Cleaning and Repairs
Pressure wash the exterior to remove loose paint, dirt, or chalky residue. Repair cracks, seal openings, and replace rotted wood. Eliminate any mold or mildew growth. The surface must be clean, dry and in sound condition before painting.
Priming
Apply primer to any bare wood, metal, or masonry. Priming enhances paint adhesion and provides a protective base coat. For hot climates, reflectivity-boosting primer is ideal to reduce thermal heat gain.
Paint Application
Fully follow the manufacturer's recommendations for application coats, drying time, temperature range, etc. Use high quality application tools. Applying paint too quickly or in too thick a coat can cause problems with appearance and performance.
Hiring a Professional
Consider hiring a professional painter, especially for large homes. Experienced painters are familiar with the specialized techniques and equipment to apply solar reflective coatings most effectively.
Look for painters who follow industry best practices and safety standards. Ask for referrals and reviews to choose a high quality pro painter in your area.
Top Heat Reflective Paint Brands and Products
Here are some of the top brands that offer solar reflective exterior paints ideal for hot climates:
Sherwin-Williams
Sherwin-Williams Duration and Emerald lines include paints featuring their proprietary Heat Reflective technology. Available in a variety of colors, these products offer solar reflectance up to SRI 85 along with fade resistance, flexibility and protection against moisture damage.
Benjamin Moore
Benjamin Moore's Aura(r) Exterior Paint features solar reflectance up to SRI 81. It utilizes color-fast pigment technology for fade resistance. Benjamin Moore also has Ultra Spec(r) EXT, a more affordable acrylic paint, in reflective Accent Base options.
Behr
Behr Premium Plus Ultra exterior paints are formulated with solar reflective pigments to reduce heat absorption. They offer UV resistance, protection from gloss fading, and high SRI ratings up to 82.
The intense heat, sunlight and temperature swings in hot climates can quickly degrade exterior paints not designed for these conditions. Choosing exterior paints with solar reflectivity, UV resistance and durability is key to maintaining your home's appearance and efficiency.
Look for high-quality acrylic or elastomeric paints with solar reflectance index of 78+ for optimal heat reflection. Prepare surfaces thoroughly and apply paint properly in adequate coats. With the right exterior paint, you can keep your home cooler, reduce energy costs and prevent frequent repainting in hot weather.
Consulting with a professional painting contractor is wise to ensure you select the ideal paint for your specific climate challenges. Proper application by experienced painters will provide longer-lasting protection and performance.
Investing in the best heat reflective exterior paint helps maintain your home's comfort and curb appeal through blistering summers. With a cool, solar reflective painted surface, you can reduce heat gain and enjoy energy savings for years before needing to repaint.