The concept of cool roofs is thrown around a lot these days. U.S. Energy Secretary Steven Chu suggested that painting roofs white, along with making paving more reflective, would reduce global warming as much as taking every car in the world off the road for 11 years. Yes, he was being hyperbolic, but he does have a point. Dark roofs absorb the sun's heat, and in hot climates, a lighter colored roof can cut down on the amount of air conditioning needed.
