Will My Metal Roof Rust?
Metal roofing has become a preferred choice among homeowners. It offers a wider range of benefits such as a longer lifespan, energy efficiency, and the ability to better withstand extreme weather conditions when compared to traditional roofing materials. It’s fire and pest resistant and is available in a variety of colors and styles, making it ideal for any type of construction project. However, many homeowners want to know: will my metal roof rust?
Rust Resistant Properties
There are a lot of different types of metals like steel, copper and aluminum, for example, that are used in roofing materials. But only metals that contain iron, like steel can rust. Aluminum is actually a naturally occurring chemical element that is often considered the world’s most abundant metal. It’s naturally rust-resistant, durable, lightweight and recyclable which is why Aluminum is one of the most popular metal roofing materials. On the other hand, steel needs to be galvanized in order to prevent corrosion. The protective galvanized coating prevents oxidation and rust. When considering a steel roof, make sure the roofer uses galvanized steel. Since copper and tin doesn’t contain iron they are naturally rust-resistant, but they are susceptible to tarnishing, especially in coastal climates.
Protecting Your Metal Roof
There are a number of protecting coatings that will protect your metal roof from rust and corrosion.
Zinc – Commonly known as galvanization, steel is coated with a layer of zinc oxide to make it rust-resistant. One of the benefits of galvanized steel is that its long lasting, about 25 to 50 years. It also requires very little maintenance.
Aluminum – Aluminum is highly resistant to rust and by coating steel with it, you’ll have an added layer of protection to prevent the steel roof from rusting. This way, you’ll have a long-lasting roof without worrying about any corrosion.
Zinc, Silicon and Aluminum – Rather than using zinc and aluminum on their own to coat steel, these two can be combined with silicon to offer additional benefits. Also known as galvalume, it was patented by Bethlehem Steel in 1972. It provides enhanced rust resistant protection, especially for metal roofs in coastal cities where the salty air can wreak havoc on an unprotected roof.
How Often Should the Protective Coating be Reapplied?
The coatings used during manufacturing may eventually lose their protection capacities, and your metal roof may need to be re-coated. The coating used to maintain your metal roof should have the same qualities as those used in the manufacturing process. Generally, you should re-coat 5 to 12 years after your roofing installation. It will all depend on your home’s size and geographic location, as these factors affect how long the initial coating lasts.
To determine if your metal roof needs re-coating, talk to a roofing professional. They can inspect your roof and help determine if the protective coating needs to be re-applied.
To prevent rust, invest in a metal roofing material that is naturally resistant to rust such as aluminum or a galvanized steel product that has been treated to prevent oxidation.