Residential metal roofing materials include steel, aluminum, stainless steel, copper, zinc and alloys of several metals. Steel and aluminum are the most commonly used metallic roofing materials. Stainless steel and copper roofs are expensive, so they are less preferred.
Aluminum makes a good metallic roofing material because it is lightweight unlike steel. It is rust resistant, though it is often painted to improve its appearance. Steel is heavier than aluminum and sturdier, so it doesn't dent easily. However, it is not rust resistant and has to be coated.
Copper, stainless steel and zinc are often used without any coating. Copper's distinctive patina and its durability makes it a preferred choice as a high-end roofing material. Stainless steel's bright silver metallic shine and resistance to corrosion makes it a preferred choice as well.