Abstract: A composition for a Coating System (paint) which forms an insulating material being designed to both reflect infrared radiation and have reduced thermal conductivity. The coating system may be either a single Thermal Coating or may be a Thermal Coating used in combination with a Thermal Primer. The Thermal Coating is formulated using conventional techniques and a resin used in paint manufacture, but utilizes primary pigments and extender mineral pigments which preferentially reflect in the infra red area of the solar spectrum. A method of characterizing particulate materials for their infra red reflectivity is described, which provides a means for preferential selection of particulate additives based on their relative visible light and infrared reflectivity. Additionally the incorporation of hollow micro-spheres is desired to reduce thermal conductivity.