Choosing a metal roof involves a lot of factors, but one of the most important is environmental. Not every metal is right for every climate. We’ve made a list of the pros and cons of some popular roofing metals to help make your decision easier.
Galvalume roofing is a combination of steel, aluminum and zinc. Together, these three metals have a lot to offer homeowners. The pros of Galvalume roofing are:
• Color options. Galvalume roofing comes in a wide array of colors to match any decor.
• Resists corrosion. The combination of metals combines the strength of zinc with the corrosion-fighting properties of aluminum, creating a strong combination.
• Ideal in wet climates. Due to the special treatment to ward off corrosion, Galvalume roofing is the best choice for wet climates.
The downsides include:
• Oil canning. Oil canning ( a buckling of sheet metal) sometimes happens to light-gauge cold-pressed metal used over large areas. It can happen to any type of metal roof but is minimized with installation by a professional trained to compensate for this phenomenon.
• Fading or chalking. The color on a Galvalume roof will fade over time. The paint used and exposure to the elements determine how fast the process happens.
Aluminum is the third most abundant metal on the planet, making it a great choice for your new roof. It is a great choice for coastal communities and also stands up to harsh winter conditions. Here’s a look at some of the benefits of an aluminum roof:
• Easy Installation. Aluminum is one of the more lightweight metals, allowing contractors to easily install it on your roof.
• No rust or corrosion. Aluminum has a protective coating to protect it from rust and corrosion. It is resistant to salt and seawater conditions, unlike other metals.
Downsides to aluminum roofing include:
• Discoloration. Aluminum does not hold its color over time. Most contractors do not recommend purchasing aluminum in its natural state due to the effects of weathering.
• Denting. Aluminum tends to dent more easily than some other metals. If your roof is under a tree or if you live in an area that is subject to hail, it could receive large amounts of damage.
• Expansion in the heat. Aluminum expands and contracts almost twice as much as steel. This can cause oil canning, a shift in the roof, and a greater need for repairs. Aluminum performs best in a climate with a steady temperature.
The Romans used copper on the roof of the Pantheon in 27 B.C. Since then copper became one of the most widely used roofing materials in the world. It has a variety of benefits including:
• Durability. Copper can last 100 or more years in all weather conditions.
• Beautiful color. The color of copper roofing is aesthetically pleasing to a home’s decor.
• Sound management. Copper is a good choice in climates prone to rain. The soft metal is much quieter in a rainstorm than some of the other options available on the market.
Some drawbacks of copper roofing are:
• Very expensive. Copper is not as abundant as other types of metals, making it more expensive as a roofing option.
• Not good in a humid environment. Copper does not weather well in a moist and humid environment. It will oxidize faster, abandoning its gorgeous color.
• Patina. Patina is the greenish-blue coating which forms on the outside of copper. Think of the Statue of Liberty. Depending on the climate, the patina will change colors. Patina can be either a positive or a negative of copper. Most homeowners prefer the copper coloring, but the patina helps to protect the metal from corrosion.
One final environmental concern of all metal roofs is ice dams. There does not seem to be one type of roof more prone to ice dams than any other, but because of the rapid cooling of a metal surface, ice dams can form on metal roofing. Typically, they cannot freeze on the slippery surface, but they can build up in particularly harsh climates.
Choose the type of metal roof with the most benefits for your region. Making the wrong choice will lead to roof damage and discoloration. If you have any questions, it is best to consult a professional.