Metal is a durable building material, and it makes for a long-lasting and beautiful roof. However, metal has one weakness, and that is rust. Metal roofs may not rust as fast as they used to, and your home probably won't look like an abandoned barn, but you may need a roofer to check your roof every few years and make repairs so the rust doesn't spread and make holes in the metal. Here's how rust affects different types of metal roofing.
Steel Roofs May Rust When The Topcoat Wears Off
Steel is a common metal roofing material because it's heavy, strong, and durable. Steel rusts easily, but when it's used for roofing, the steel is treated to slow down the rusting process. Steel is often treated with zinc, but other materials might be used too. Then the roofing is topped with a coating for extra protection.
Instead of steel oxidizing and rusting, the topcoats have to deteriorate first, and this gives your roof a longer life. However, if the topcoat wears away or gets scratched off, rust might start to form. However, a roofer that does metal roofing repair can scrape off or sand off the rust and cover the metal with another coating, and this stops the rust from spreading.
Aluminum Resists Rust
Aluminum roofing is resistant to rust since metal needs iron in it to rust. However, aluminum can corrode in certain circumstances, and your roof could still develop problems with rust in the fasteners used on the roof. A roofer can check screws and fasteners when inspecting the roof and replace ones that have rusted.
Zinc Develops A Protective Patina
Zinc roofing is even more rust resistant than aluminum metal roofing. Zinc doesn't rust, but it does oxidize and form a patina. The patina is considered a desirable and attractive look for metal roofing, and as a benefit, the patina protects the zinc roof from rust. A downside to zinc roofing is that it is expensive.
Copper Roofing Oxidizes But Doesn't Rust
Copper is another expensive metal to use for roofing. Copper doesn't rust since it has no iron, but it does oxidize. When copper oxidizes, it develops a patina that gives the roof a blue or green color that's considered attractive.
Steel and aluminum are the most popular options for metal roofing since they are the most affordable. Consider the environment around your house when choosing the right metal for your roof. If your house is on a large lake, bay, or ocean, it may rust quicker than if your home is in a dry area.
Removing rust is a fairly easy type of metal roofing repair, but it's good to have the rust removed before it spreads and makes your roof look ugly. A roofer can remove the rust by sanding it off, and if the rust has eaten a hole in the metal, the hole can be covered with a metal patch.
For more information, reach out to a metal roofing repair service.