Considerations in Formulating and Using COOL ROOFING COATINGS

White, cool roofing coatings are associated with reduced heat build-up of roofing surfaces and are directly correlated to the lowering of utility bills associated with the cooling costs for the buildings which utilize them. White coloration, however, is not the only criterion to use in judging whether a cool roofing coating will be effective. An efficient cool roof is a system combining the coating formulation and the underlying substrate, exposed to the elements. Using measurement of solar reflectivity and resulting heat build-up (temperature rise), the effect of TiO2 grade, extender content, substrate type, and dirt condition of the paint film surface is discussed in terms of its ability to retard temperature build-up.