Could a light-colored roof boost the energy efficiency of your home?
An energy-efficient home has many benefits. You’re likely to experience high and low temperatures more comfortably, save money on utilities, and have a higher resale value than similar non-efficient homes. But does the color of your roof’s shingles affect energy efficiency?
It turns out that, while a light-colored roof is slightly more energy-efficient than a darker-colored roof, other factors play a much bigger role in energy efficiency. Key factors to consider when thinking about your roof’s energy efficiency include reflectivity, roofing materials, coating, ventilation, and insulation.
Which Color Roof Has the Best Energy Efficiency?
If your top priority in a new roof is energy efficiency, selecting a roofing color that’s as light as possible will maximize your efforts. Most roofing shingles and materials come in a variety of colors, with lighter versions beating out darker versions on energy efficiency every time.
The Most Energy-Efficient Roofing Colors Include:
White
Light gray
Light tan
The Least Energy-Efficient Roofing Colors Include:
Black
Dark gray
Dark brown
What Is a Reflectivity Rating?
A roof’s reflectivity rating is a measure of the roof’s ability to reflect rays from the sun. In general, roofs with higher reflectivity ratings (over 65%) are better at reflecting the sun’s rays and keeping your home cool during warmer months.
If all materials are equal, then lighter roofs (like white, light gray, and light tan), tend to have a higher reflectivity rating. A reflectivity rating is not the only measure of a roof’s energy efficiency, but it is a good place to start. While you won’t be able to check your roof’s reflectivity rating on your own, a roofing professional will be able to give you the information you need.
Which Roofing Materials Are the Most Energy-Efficient?
Roofing can be made from a variety of materials, each of which will create more or less energy-efficient conditions. Popular roofing materials that can boost energy efficiency include metal, composite, and some asphalt options.
Metal Roofs
Metal roofs have a high reflectivity rating and naturally dissipate heat. Researchers with the U.S. Department of Energy calculate that metallic roofs as either shingles or panels can lower your air conditioning costs by up to 25%. While the exact numbers are tough to run, in general, lighter-colored metal roofs are more energy-efficient than darker-colored metal roofs.
Composite Roofs
Composite roofing, which is roofing made of recycled materials and often designed to look like slate roofing, often comes in energy-efficient varieties. When considering composite roofing, choosing a lighter color will give you more bang for your energy-efficiency buck.
Asphalt Roofs
Around 75% of homes across the United States have asphalt shingles on their roof. While this popular roofing material is durable and affordable, its energy efficiency varies greatly.
Homeowners who have high-quality, energy-efficient asphalt shingles can usually see a notable difference in their home energy bills. So, too, can homeowners who switch from darker-colored shingles to lighter-colored shingles.
Can You Improve Energy Efficiency With Roof Coatings and Paints?
If you want to boost your roof’s energy efficiency, using roof coating or paint can help. Some roof coatings will make the roof a lighter color, such as white, or use special reflective pigments that reflect the sunlight.
Others will provide more solar heat reflectivity. This reflectivity can help with energy savings in warm weather and especially during summer months.
Not all roofs are suited to coating or painting. You should not coat or paint your roof if:
Applying paint or coating will negatively affect or void your roof’s warranty
You have an asphalt roof (coating cannot be applied to asphalt)
Your roof already comes with a cool roof coating (like most metal roofs) and you notice no chipping or peeling
Your roof already comes with a cool roof coating (like most metal roofs) and you notice no chipping or peeling
If your roof is a good candidate for coating, your pro will probably use an elastomeric coating. This sort of coating is thick and provides waterproof protection in addition to heat and UV ray resistance. Elastomeric roof coating costs $0.15 to $0.75 per square foot and is a budget-friendly option.
What Sort of Roofing Products Should I Look For?
If you’re planning to take your roof's energy efficiency up a notch, you’ll want to be sure that any roof products, such as tiles, shingles, or roof coatings, are Energy Star rated.
Energy Star-rated products are guaranteed to meet minimum solar reflectance values, which lower your peak cooling demand by 10% to 15% and will help you save on your energy bill.
What Else Impacts My Roof’s Energy Efficiency?
While your roofing materials and any paint or coatings you have will have a significant impact on your roof’s overall energy efficiency, those aren't the only factors that matter. The insulation and ventilation in your attic are especially important in contributing to your home’s temperature and need for warm weather cooling.
If you find yourself sweating every time you head to the attic to pull down your holiday decorations, you might need to investigate your ventilation and insulation situation. Having a properly insulated home, good attic ventilation, and a high-quality roof help with your overall energy efficiency.
What Else Should I Consider?
Energy efficiency is important, but you’ll need to pick a roofing material that fits your other criteria as well, such as cost, quality, and durability. You also want to pick a roof color that matches the style of your home and your personal preferences.
As you weigh your options, you might appreciate professional guidance about your priorities and options. A local roofing pro can evaluate and talk with you about how to create a roof that is as stylish, functional, and as energy-efficient as possible.
