A cool roof is a roof or roofing system that has the ability to reflect a majority of the sun’s heat away from the roof while radiating the small percentage of heat absorbed by the roof surface. Cool roofs come in many different colors; however, a white surfaced rooftop has the greatest ability to reflect the most amount of sunlight away from the building. The concept is similar to wearing a light colored shirt versus a dark colored shirt. The lighter the shirt - the cooler you feel on a hot day, the darker the shirt - the more heat you absorb therefore, the hotter you become.
Cool roofs are favored by building tenants and owners because they are able to keep the inside air temperature of the building cooler without using the air conditioning as often. This is an excellent way for building tenants and owners to save a great amount of money on their energy utility bills and put less stress on their HVAC equipment, allowing them to last longer.
There are several different roofing products available offering cool roof technology, how do you know which one’s will perform best? The Cool Roof Rating Council or CRRC is an excellent independent, non-biased organization that has established a system for providing Building Code Bodies, Energy Service Providers, Architects & Specifiers, Property Owners and Community Planners with accurate radiative property data on roof surfaces that may improve the energy efficiency of buildings while positively impacting our environment. They determines the “coolness” of a roofing product based on Solar Reflectance (SR) the portion of the suns’ heat that is reflected by the roof and Thermal Emittance (TE) the capability the roof surface has to radiate the heat absorbed by the roof. The CRRC records initial testing values and aged (3-year) testing values to determine the capabilities the product in question has to perform. Visit their website (www.coolroofs.org) for a complete rated products directory ranging from asphalt roofing, roof coatings, single-plies, metal and more.
If you are interested specifically in highly reflective roof coatings and roofing systems, National Coatings has nineteen fluid-applied coatings and systems tested and rated by the CRRC. Our AcryShield roof coatings are some of the highest rated products listed in the directory for solar reflectance, thermal emittance and SRI (Solar reflectance index) the measure of solar reflectance and thermal emittance which is used as a guide to determine how much solar heat the roof is capable of discarding. For a full listing of our Cool Roof Rating Council Compliant Products, click here.
Interested in more information on Cool Roofing? Download our FREE Cool Roof Jargon brochure!