Metal Roofing Materials. Metal roofing materials can last for decades without degrading in appearance or function. The oldest metal roofs in the world are over 120 years old and are still in fairly good condition. Paint and anti-rust technologies increase a metal roof’s lifespan drastically and make metallic roofs an excellent long-term investment. Residential metal roofs typically have a rated lifespan of 50 years or more. This is outstanding compared to the 15-year average lifespan of other materials.