Many people know that the color of the exterior paint of your home can impact indoor cooling costs in hot climates. A dark color absorbs heat, which makes the inside of your home warmer. Lighter colors reflect the sun's heat, so it's easier to keep it cooler inside. But did you know that the choice of paint can have an even bigger impact? New exterior paints use thermally reflective technology that blocks heat radiation over a broad spectrum. Using specialty paint and choosing a light color can reduce cooling costs by around 20 percent.