Protection for Metal Roofs, Even If Rust Has Started Your metal roof isn’t failing, it is simply exposed to the elements. Light rust does not mean you need a replacement, just that the surface needs the right protection. Our MetalSafe Sealant is formulated specifically for metal roofs and contains built-in rust inhibitors to help prevent corrosion from spreading. As long as the roof is cleaned first, Liquid Rubber’s MetalSafe Sealant can be applied directly over lightly rusted areas, no primer required. This flexible, waterproof, UV-stable coating forms a durable barrier that seals out moisture while helping protect against further rust. It goes on brown and dries black for a bold look. Read the full Application Guideline for materials needed, coverage details, and more, before starting your project.