Residential metal roofing is generally made of steel, aluminum, or copper. Although this does mean it is more expensive than traditional shingle roofing, metal roofing does have a much longer lifespan. In order to prepare for installation, rolls of 24- or 26-gauge steel sheets are given a metallic coating to prevent rust, followed by a baked-on paint finish. This paint finish can be customized to a color that fits the overall look of your home. Steel roofing products are coated with either zinc (galvanized) or a mixture of aluminum and zinc. The coatings are offered in multiple thicknesses—the thicker the coating the longer the life, and the higher the cost.