Whether you're buying a home with one or thinking of installing, here's what to know.

Whether you're putting a roof on a new home, or your existing roof requires a total makeover, there are many materials available. But no matter what roof style you have metal roofs can be an attractive option because of their longevity, minimal maintenance, and energy efficiency. And you can choose from tin, zinc, aluminum, copper, or galvanized steel — just make sure your metal roofing material is tested and labeled by UL, FM Global, or the equivalent, and that you check with your local building department for any code requirements.

Advantages of metal roofs

Metal roofs offer many benefits, including:

• Longevity. Metal roofs can last 40-70 years, depending on the material. Traditional asphalt roofing materials have an estimated life expectancy of roughly 12-20 years.
• Durability. Some metal roofs can sustain wind gusts up to 140 miles per hour, will not corrode or crack, and may be impact-resistant (depending on which metal you choose). In addition, metal roofs don't need the periodic costly maintenance that other roofing materials often require. However, they should be inspected periodically to make sure no repairs are required.
• Safety. Metal roofs will not spark and ignite into flames during a wildfire or lightning strike.
• Energy efficiency. Metal roofs reflect solar radiant heat, which can reduce cooling costs by 10-25%.
• Environmentally friendly. Metal roofs not only have 25-95% recycled content, depending on the material used, but are also 100% recyclable at the end of their life as a roof. In contrast, most shingle tear-off waste ends up as part of the building-related waste stream — up to 20 billion pounds per year.

Disadvantages of metal roofs

Despite their many advantages, metal roofs have some potential drawbacks.

• Affordability. Metal roofs can be as much as two or three times more expensive than other roofing materials. While the life of a metal roof is much longer, investing in a metal roof only makes sense if you plan to stay in your home long enough to enjoy the cost benefits.
• Noisiness. Metal roofs can be noisy, especially during a heavy rain or hailstorm. Adding more insulation during installation usually solves this problem, but that may increase costs.
• Expansion and contraction. Metal roofing materials that are attached as large panels tend to expand and contract. If they are not properly installed with fasteners that allow the metal to "breathe," the panels may loosen.
• Inconsistency of color match. If a repair is required or a home extension is added years later, it may be difficult to find an exact match to the existing metal.
• Performance. If water accumulates anywhere on the roof because of poor-quality installation or repair, it can eventually cause serious damage. Low-grade metals may also be thinner and less durable. Some metals rust in certain climates or dent more easily than others during hailstorms or installation.