A metal roof can last anywhere from 15 to over 100 years, with an average of 50 years, depending on the material, installation, and environment. The specific metal is a key factor: aluminum roofs may last 20 to 45 years, while steel can last 30 to 60 years. Tin can last for up to 75 years, and more durable options like zinc, stainless steel, and copper can last from 80 to over 100 years. Factors that can shorten a metal roof's lifespan include living in a coastal region with corrosive salt air, improper installation (such as laying over old shingles), and failing to inspect and replace fasteners, which may wear out before the panels.

The best kind of tarp for a roof is one that will stand up to the elements, weather, and sun. Viny roof tarps are known for their durability and resistance to water, tears, and mold—making these tarps a good choice for use in winter conditions and the summer sun. Polyethylene tarps are also quite durable and waterproof.

Some people prefer to use connectors consisting of galvanized metal to replace the birdsmouth cuts on the rafter board. Common names for these metal pieces include hurricane ties and variable-pitch connectors. Making birdsmouth cuts is more cost-effective than purchasing these connectors for each rafter. However, because making large birdsmouth cuts to accommodate extra-wide exterior walls can weaken the rafter, a connector may be the better option in some cases.

Whether replacing the entire roof or just installing roof shingle replacements in small areas, always pull up the old roof shingles. While you can technically put new roof shingles (but not other roof materials) over old shingles, this can add weight strain to the roof and prevent the new shingles from securing properly to the roof.