The Gerard Stone Coated Steel Roofing System reduces heat gain by as much as 45% over conventional asphalt roofing. Gerard uses highly UV-reflective granite stone chips which are sealed to the tough Zinc-Aluminum steel sub straight. The Gerard system allows air to pass between the deck and the panels. When air convection is combined with the highly reflective Gerard steel and stone roofing the result is one of the most energy efficient and eco-friendly systems in the world.