Do Metal Roofs Rust?
Metal roofing is an excellent choice for homes and businesses in Ohio, offering durability, style, and energy-efficiency. However, some homeowners are hesitant to install metal roofs because they’re concerned about rust. So how worried should you be about rust?
Do Metal Roofing Panels Rust?
Do metal roofs rust? The answer depends on what type of metal the roof is made of. All metals than contain iron are susceptible to rust. However, most modern roofs are coated to prevent rust. Zinc, aluminum, and galvalume coatings can keep a metal roof protected for years. Plus, not all metals contain iron. Since rust is a chemical reaction that occurs between iron, oxygen, and water, metals that don’t contain iron are rustproof!
Types of Metal Roofs
Your roof’s risk of rusting depends on what type of metal it is. Here’s a quick guide to some of the most popular metal roofing materials:
Steel is a combination of iron and carbon, so it will rust if it doesn’t have a protective coating. Luckily, there are plenty of zinc, aluminum, and galvalume roof coatings that can protect steel roofs from rusting. You’ve probably heard of galvanized steel—this is steel that has been coated with zinc.
While stainless steel is made of iron, it also contains chromium, which is corrosion-resistant. Chromium protects stainless steel from rusting by combining with oxygen molecules before the iron does. The more chromium in stainless steel, the better.
Aluminum is rustproof because it doesn’t contain iron. Some manufacturers might add small amounts of other elements to aluminum roofing products to make them stronger, but by itself, aluminum doesn’t rust. In fact, aluminum is used in roof coatings to protect other metals from rusting.
Bronze doesn’t rust because it contains very little iron. However, bronze reacts to oxygen in other ways. Since bronze is a combination of copper and tin, it’s not completely immune to corrosion. This means its appearance will change over time. When bronze corrodes, its surface turns green. Luckily, there are plenty of bronze coatings that can prevent bronze disease.
Copper also doesn’t contain enough iron to rust. However—copper will oxidize and form a green film, just like bronze. Some homeowners prefer this look to the original appearance of copper; it gives it character! However, if you prefer the look of unoxidized copper, there are plenty of copper coatings you can use to prevent oxidization.
Types of Metal Roof Coatings
If you want to maximize the lifespan of your metal roof, you should have it installed and coated by a professional roofing company. Roof coatings can stop leaks, prevent rusting, and reduce energy consumption. Two of the most popular metal roof coatings are zinc and galvalume:
Zinc is one of the most common coatings applied to metal roofs to prevent rusting. The process of adding a zinc coating to steel is called galvanization. Galvanized steel is finished with a resin coating, which gives the final product a shiny finish.
Patented by Bethlehem Steel in 1972, galvalume is a coating made of zinc, aluminum, and silicon. The combination of these three elements makes galvalume more durable and corrosion-resistant than zinc or aluminum alone. Galvalume gives metal roofing panels a matte finish.
How Often Should Metal Roofs Be Recoated?
In general, metal roofs should be recoated every 5 to 12 years, but it depends on the quality of the coating and how well it’s applied. This is why it’s important to work with a professional roofing company that has experience with metal roofs. A properly coated metal roof will be protected from rust for years. However, a building’s size, location and function can also influence how often your metal roof needs recoated. At DeMarco Inc, our team takes all of these factors into consideration when determining our recommendation for recoating.
Metal Roofing Benefits
Now that we’ve explained why rusting isn’t an issue for most modern roofs, let’s talk about some of their other benefits. Metal roofs offer durability, style, energy efficiency, and more:
When installed correctly, metal roofs can withstand strong impacts and wind speeds over 100 mph. Metal roofs have a lifespan of 40 to 70 years, depending on the material. To put this in perspective, traditional asphalt roofs have an estimated lifespan of 12 to 20 years.
Metal roofs reflect sunlight to keep your building cooler during the summer months. They’re also environmentally friendly. Metal roofs are often made of recycled materials and the panels are 100% recyclable when they need to be replaced.
Metal roofing panels come in many different materials, sizes, styles, and colors. With so many customization options, you’re sure to find a look that suits your building. Metal roofs are also much easier to paint than asphalt roofs.
Metal roofing panels don’t require much maintenance. Since metal roofs are extremely durable, they don’t require much upkeep besides removing leaves and debris. Although they’re low-maintenance, you should still have your metal roof inspected once or twice a year to spot damage early.
Metal Roofing Drawbacks
You shouldn’t worry too much about a metal roof rusting, but there are some real drawbacks to metal roofing materials. Here are a few cons to keep in mind:
Metal is more expensive than other roofing materials. A metal roof is a great investment if you’re planning on staying in your home or building for a significant period of time, but if you’re looking for a cheap roofing material, metal isn’t your best option.
Metal roofs are nosier than other roofing materials when it rains. Some homeowners like the sound of rain on a metal roof, but if you want a quiet roofing material, metal isn’t your best option. If you have the budget for it, attic insulation and insulated metal panels can make a metal roof quieter during storms.
Metal panels are impact-resistant, but they can be dented if a heavy object falls on them. You should take steps to prevent heavy branches from falling on your metal roof. Hail can also dent metal panels.
Panel Expansion and Contraction
A unique characteristic of metal roofing is that the panels expand and contact when they get warmer or colder. Metal roofing systems are designed to accommodate these expansions and contractions, but the fasteners, washers, and screws can degrade and become dislodged over time.
How Long Do Metal Roofs Last?
The average metal roof has a lifespan of 40 to 70 years, but it depends on the material. For example, some copper roofs have lasted over 100 years! Other factors that influence a metal roof’s lifespan include the quality of its installation, weather conditions, and your maintenance habits.
The quality of your metal roof’s installation is one of the most significant factors that will influence its longevity. When a metal roof is properly installed, it’s much less vulnerable to leaks, oil canning, and other types of damage.
Metal roofs are extremely resilient against the elements, but all roofs are impacted by the weather. If you live in an area that experiences a lot of rain, snow, and strong winds, you should know that these conditions can reduce the lifespan of your metal roof.
Metal roofs don’t require much maintenance, but it’s still a good idea to inspect them once or twice a year. Keeping your metal roof clear of standing water, leaves, tree branches, and other debris will keep your roof in the best shape possible.
Contact Us Today for Metal Roofing Installation and Repair
Contact us today for metal roofing in the Columbus area. We’ve been serving residential and commercial customers in Columbus, Ohio for over 30 years. You can rely on our team for quality work, whether you need a new roof or repairs on an existing roof. Contact us today to request a quote on a new standing seam metal roof.
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1160 South Front Street, Columbus, OH 43206