Cool Roof System Advantages:
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Elastomeric Cool Roof Systems save energy, improve our environment and save money.
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Cool Roofs often eliminate the requirement to "tear-off" the existing roof, thereby reducing roofing costs and roofing debris hauled to land fills.
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Elastomeric Cool Roof Coatings provide superior weather resistance, UV resistance, and resistant to mold and mildew.
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Cool Roofs are designed to reduce the cooling load on a building by reflecting the sun’s energy away from the roof surface. This reduces the amount of solar heat gain that the building’s cooling system must overcome, and in return, lower energy costs and improve building comfort.
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All studies confirm the ability of cool roof coatings to reduce roof temperatures dramatically - by 50 to 80 degrees F, saving between 20 and 70 percent of the cooling energy used in a building.
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Many Cool Roof systems are renewable. Asphalt products by themselves undergo a degradation process which is caused by high temperature and ultraviolet sunlight. Cool Roof products tend to protect a conventional built-up roof much better because they have UV inhibitors built into their formulation. Once a Cool Roof system using a fluid-applied coating has been in service for 10 years, it can easily be pressure washed and then recoated with a single coating application, and a new warranty issued to the building owner, making this type of Cool Roof system both durable and affordable.
Cool Roof Solar Reflectance & Thermal Emittance
It is common experience that objects in the direct sun become hotter than others. This is true for roofs. One could comfortably touch one roof yet find the touch of another uncomfortable under the same climatic conditions. Just how hot a roof gets depends on the roof surface solar reflectance and thermal emittance.
Solar reflective "albedo" surfaces are often thought of as being “bright white”. Traditional roofing materials have a low solar reflectance of 5 to 15 percent, which means they absorb 85 to 95 percent of the energy reaching them instead of reflecting the energy back out to the atmosphere. The coolest roof materials have a high solar reflectance of more than 70 percent, absorbing and transferring to the building 30 percent or less of the energy that reaches them. Traditional roofs easily reach temperatures of 165F during clear, sunny conditions.
While solar reflectance is the most important property in determining a material's contribution to urban heat islands, thermal emittance is also a part of the equation. Any surface exposed to radiant energy will get hotter until it gives off as much heat as it receives (thermal equilibrium). A material's thermal emittance determines how much heat it will radiate, or how readily a surface
gives up heat. When exposed to sunlight, a surface with high emittance will reach thermal equilibruim at lower temperatures because the high-emittance surface gives off heat more readily.
The prevalence of asphaltic materials in built-up roofs means that many existing low-sloped roofs are dark in color and have a low solar reflectance. The most notable examples of reduced energy costs come from replacing traditional roofs with white roofs on buildings with high air conditioning loads. The prospects of reduced energy costs, along with the lower surface temperatures of a white surface, have been instrumental in creating a strong demand for high reflectance, elastomeric roof coatings.
Sustainability’s Impact
Sustainability is an increasingly popular and widespread force in the facilities market. GREEN building programs and trade shows have drawn significant interest and enthusiasm from architects, building owners, and managers, increasing the demand for environmentally friendly GREEN products.
As environmental considerations affect building designs and as managers strive to save energy and money, cool roofing products have gained momentum. The combination of energy savings, less maintenance and increased comfort can make cool roofing products a cost-effective measure.
More often, these products are specified for new construction and re-roofing projects to comply with building codes or to simply improve building efficiency and lower a roof’s life-cycle costs.
Cool Roofing continues to have a monumental impact on the roofing marketplace. Building energy codes, such as California Title 24, demonstrate that this is no passing phase. Instead it is a lasting, beneficial addition to sustainable building.
