A reflective roof coating is applied to roofs to help reflect more sunlight from the surface, thus reducing the amount of heat absorbed by the structure. Also known as cool roofing, these roof coatings are available in a number of colors, surfaces, and thicknesses and can make a huge difference when it comes to saving money on energy costs and usage. On top of that, they also aid in creating more comfortable indoor environments, and play a role in prolonging the life of roofs and roofing materials.
Reflective Roof Coating 101: How a Reflective Roof Coating Works
Cool roof coatings work to keep your home cool in two distinct ways. The first is by solar reflectance, or the coating’s ability to reflect sunlight away as soon as it hits your structure. Instead of absorbing the sunlight and heat like a traditional roof, a cool roof reflects the light and heat away from your home, keeping your home cooler in the process. The other way that cool roofing helps to keep your home cooler is through thermal emittance. These roof coatings are now made with special materials that increase your roof’s thermal emittance level, or your roof’s ability to radiate absorbed heat back into the atmosphere instead of down into your home. It’s this potent combination of high solar reflectance and thermal emittance that make these roof coatings so effective at keeping your home cool and your energy costs and usage down.
Reflective Roof Coating and Energy Savings
What kind of energy costs and usage savings are we talking about here? Significant ones. It’s important to realize that the amount of benefits you get from your reflective coating will vary depending on the shape of your home, the coating you choose, how energy efficient your home already is, your local climate, and whether you use air conditioning or not. However, if you live in a hot climate that experiences warm temperatures and sunny days for a substantial portion of the year, you can expect energy savings of up to 70%. If not, your energy savings from applying a reflective roof coating could range anywhere from 20% to 70% when it?s all said and done.
Ready to start your reflective roofing?Find Pros
Shopping for a Reflective Roof Coating
The most important decision you’re going to make when shopping for cool roof coatings is the color. Reflective coatings come in white, a variety of darker colors, and in high reflection coatings. What you decide on here can make a huge difference. White coatings are by far the most effective, and reflect anywhere from 50% to 90% of the sunlight and heat that hit your roof. Highly reflective coatings, which most often resemble a paintable aluminum coating, come in second with reflectance levels in the 60% to 70% range. And if you decide to choose looks over performance, colored coatings significantly reduce the reflectivity ratings to 15% to 35% (which is still better than no coating at all). When you make your decision, keep in mind also that if your new roof coating reflects enough light and heat (65% for flat roofs and 25% for sloped roofs), it will also qualify as an Energy Star rated roof and will earn you tax breaks on top of the high energy savings.
Application and Other Improvements
These coatings can be applied on your own, you can hire a professional to do the job for you, or you can look for roofing materials that have reflective coatings already baked onto the surface. And if you’re serious about improving the energy efficiency of your home, talk to an energy auditor or general contractor about other modifications you can make to improve your efficiency ratings. Improving traditional insulation in your attic, installing reflective attic insulation, and improving attic ventilation are all smart steps to take, along with applying reflective coatings, in order to get maximum energy efficiency out of your home.
I am writing from Perth, Australia and my question for you is if there is an authority or a website that ranks/follows the performance of such heat reflective coatings installed on roofs or walls of buildings. they can get rated by solar reflectance index SRI, total solar reflectance TSR and emittance, which are all standardized. My question is if there is such a ranking, formal or empirical, listed somewhere at all.
Thanks, Bogdan Dana