When it comes to roofing, you have a lot of options. If you want a roof that can last a long time with little attention on your part, then you’ll want to look into very durable materials. As long as the roof isn’t perfectly flat, metal might prove to be the best option available.
There are four metals that are commonly used in roofing: steel, aluminum, copper, and zinc. We’ll go over all four and highlight their strengths and weaknesses.
So which is the best type of metal roofing?
Steel is the most affordable, but copper, zinc, and aluminum are all more resistant to corrosion. Many people find copper the most aesthetically appealing. Zinc and copper last the longest.
The Most Affordable Metal Roofing
The most common roofing material that you will find in the U.S. is steel. Steel roofing is obviously good for a few reasons. It’s incredibly strong, and it has the greatest tensile strength of any roofing metal on this list. Steel is impressive in the face of devastating weather. It’s strength and weight make it impervious to all but the very strongest wind.
Roofing steel is treated with materials that make it resistant to corrosion, so you don’t have to worry about your steel roof rusting after a little rain. There are a few treatments available, but the most common are galvanized steel and galvalume steel.
The leading reason for steel’s popularity is the cost. Steel costs less as a material than any other common roofing metal. Despite the low cost, it can still regularly last 20 to 50 years. That makes steel a great investment and a compelling choice for many roofs.
The Most Resistant to Corrosion
Any metal used in roofing is going to have protection against corrosion. Water corrodes unprotected metals, so the expectation is that the roof will have to withstand the rain. Even though every metal has some protection, aluminum roofing is the hands-down winner on this front.
Steel roofing is treated with other metals to create a protective barrier. If that barrier is damaged, the steel will rust. Copper roofing and zinc roofing (which will be discussed more in a moment) develop protective barriers naturally over time. You’re probably familiar with copper’s greenish patina, which helps protect it.
Aluminum develops natural resistance to corrosion much, much faster. The outer layer of aluminum oxidizes rather quickly, but the oxidation stops at that outer layer. The result is a barrier that prevents further oxidation. If the outer layer is damaged, the exposed aluminum will ultimately oxidize and restore the protection.
Because aluminum goes through this process much faster than zinc and copper, aluminum is a better choice for environments where it is exposed to greater corrosion risks. Aluminum is usually the top choice for use by the sea. It’s also ideal for some industrial roofing where processes would corrode other metals.
The Prettiest Choice
Copper is often regarded as the most beautiful metal used in roofing. While it starts off with its signature copper color, the metal will patina over time. What this really means is that exposure to air causes the copper to oxidize on the outer layer. That patina can take a number of colors, and it’s hard to predict how it will look exactly. That’s what most people like about it. A copper patina will always be unique.
The patina actually protects the copper against corrosion and weather. Because of that, copper is also incredibly durable in roofing. If the patina is scratched or damaged, it will expose a little more fresh copper which will then oxidize. In a sense, the patina is self-repairing, meaning copper roofs need very little maintenance.
Copper roofs are known to last well over 50 years, and there are plenty of historical buildings with copper roofs that are hundreds of years old.
All of this sounds pretty amazing, so why aren’t all roofs made of copper? It comes down to cost. While pricing depends on market conditions, copper is typically much more expensive than any other roofing metal, and most buildings don’t need roofs to last for centuries. The 50+ years of lifespan you can get from other metals is usually fine and enough to justify the less-expensive option.
The Best Metal Roofing for Durability
In reality, there are two types of metal roofing that last the longest: zinc and copper. Since we already talked about copper, we’ll discuss zinc this time around. Zinc is another metal that quickly produces its own protective barrier when exposed to air. The oxidized layer stops further oxidation or corrosion, and zinc is able to withstand indefinite exposure to water without any problems.
Zinc regularly lasts 80 years or more, and with proper care, it’s lifespan can exceed a century. It doesn’t necessarily last longer than copper. The two are really tied on this front. Zinc is arguably just as attractive as copper, and it is quite pricey. Depending on market conditions, zinc will sometimes be more or less expensive than copper, but regardless, you can expect it to be much more expensive than steel and aluminum.
Choosing the Best Type of Metal Roofing for Your Home
Ready to overhaul your roof, or make a choice for your newly built home?
Once you pick your roofing material, you’ll need experienced professionals to get it installed. At Alpine Sheet Metal Systems, we fabricate and install metal roofing of all kinds, including steel, aluminum, copper, and zinc.