Ever been up on a roof before? Did you notice how hot it gets up there?
On the ground, the temperature can feel comfortable. Up on your roof, the heat can feel sweltering at the same time.
A “cool roof” isn’t one that looks awesome (although it might) – it’s one that stays cooler in hot temperatures. And the reason you might want to install one on your new home is that it saves energy. You can reduce temperatures by up to 33% with a cool roof.
These roofs use highly reflective paint, tiles, shingles, or a sheet covering to reflect more of the sun’s rays than standard roofing.
Besides reducing energy bills, cool roofs also improve the comfort of non-air-conditioned spaces (like your attic), and a reduced temperature can also make your roof last longer.
And if you’re the selfless type who thinks of the community at large, cool roofs also:
- Can lower local air temperatures in the surrounding community
- Help prevent power blackouts and brownouts because they reduce your electricity usage
- Reduce the volume of harmful power plant emissions released into the atmosphere
Who Should Use a “Cool Roof”?
Cool roofs make sense for every Texas homeowner who can afford them. They may not make sense for people who live in the coolest and northernmost states like New York, Minnesota, Michigan, and Maine.
Cool roofs do release some heat during the winter, so you may notice a slight increase in your heating costs. However, the energy savings from reduced air conditioning costs more than outweighs the increased heating expenses.
Plus, since the sun is lower during the winter, and the snow covers your roof, and you tend to have more cloud days, the increased heating costs get minimized further.
You can use this calculator to get a more precise estimate of how much energy your cool roof might save.
How do Cool Roofs Work?
In their most basic terms, cool roofs are simply lighter colors, which reflect sunlight, versus darker colors, like shingles, which absorb more heat. Their surface temperature only gets slightly hotter than the air temperature. Compare that to a standard roof, which can get up to 150 degrees!
“Solar reflectance” determines the fraction of the total solar energy a material reflects away from your roof. Your material should have a solar reflectance of at least .25. “Thermal emittance” means how well a material releases heat it has already absorbed.
Cool Roofs Pay for Themselves in 2-3 Years!
They’re not usually expensive to install – typically just a few thousand dollars. You can make your money back on them in just 2-3 years, and then experience savings after that.
If you have money to invest in your home, consider a cool roof.