Metal Roofing Guide
Metal roofing has increased in popularity significantly over the last several years because it's durable, attractive, and saves on energy bills. In Hometown's Metal Roofing Guide, learn about advantages, disadvantages, styles, and frequently asked questions related to metal roofs.
Pro's and Con's of Metal Roofing
Advantages of metal roof installation
- Durability - Metal roofing lasts longer than shingles when installed properly.
- Long term warranties - Many metal roofing manufacturers warranty their product for 50 years or even longer. That compares favorably to asphalt shingles, which may need to be replaced every 15 to 20 years. If you compare the average annual metal roof prices to shingles, metal is competitive over the long haul because you need to repair and replace it less often.
- Lower energy bills - Metal reflects heat from the sun helping your roof and home stay cooler, using less energy.
- Fire resistant - Residential metal roofing has a Class A fire rating, which means it receives the designation of "most resistant" to fires.
- Weather resistant - Metal roofs can withstand extremely high winds and climate changes.
- No removal of old shingle roofing - In many situations, a metal roof can be installed directly over the old shingle roof. Not having to remove and dispose of one or two layers of shingles helps make metal roofing more cost competitive.
Disadvantages of a residential metal roof
- Metal roofing costs - The upfront cost of installing a new metal roof is significantly more expensive than shingle roofing. Metal roofing cost typically runs anywhere from $150 per square to $600 per square (a "square" is 100 square feet of roof).
- Possible denting - Denting and marring can happen with metal roofs. Many new metal roofs are guaranteed against denting and marring, but some are prone to damage in the right conditions, such as extremely large hail or falling tree limbs.
Metal Roofing Materials
Most of the metal roofing products available today are made of steel or aluminum. There are also specialty applications for other metals such as copper, titanium and zinc.
Steel roofing is a light weight roofing material and is covered by a protective coating to prevent it from rusting. Metallic coatings on steel roofing are either 100% zinc ("galvanized") or a mixture of zinc and aluminum ("Galvalume" or "Zincalume"). The mixed coating is the most effective at preventing rust. Depending upon the exact product chosen, steel roofs are often about 20 percent cheaper than aluminum roofing.
Aluminum roofs are even lighter than steel and do not need to go through the metallic coating process. An advantage of aluminum over steel is that aluminum is more resistant to corrosion caused by the salt spray from seawater. So if you're home is near the ocean, aluminum is the way to go. Aluminum roofs are typically a bit more expensive than steel.
Metal Roofing Styles
Today’s metal roofing systems are available in more styles than ever. Since metal can be formed into virtually any shape, you can get any style or color you have with other types of roofing, but with the advantage of increased durability metal offers. This includes shake-style roofing, shingle, slate or tile.
Metal Roofing FAQ
Why does the gauge of the metal roofing product matter?
The gauge of the metal is a measurement of its thickness -- the thicker the metal, the lower the number. On a steel roof, a 29 gauge metal roofing product is thinner than one that is 24 gauge.
Lower gauge metal roofing products are more durable in extreme weather conditions compared to higher gauge choices. Since they are more durable, lower gauge products also cost more. For residential applications, 29 gauge metal roofing or thicker (lower gauge) is recommended.
Will a metal roof rust or fade in color?
Steel roofing panels are protected by layers of metallic and polymer coatings. Industry studies have repeatedly shown them to outperform the corrosion resistance of other coated metals. The level of protection against rust or fading color depends on the grade of material. Higher grades of metal roofs offer more protection against rust and offer a higher level of paint quality more resistant to fading. Ask your metal roofing contractor to explain your options.
How does the weight of a metal roof compare to other roofing systems?
Metal roofs are surprisingly lightweight. On average, a metal roof is 50 percent lighter than a traditional shingle roof and 75 percent lighter than concrete or slate tile roofing. The lighter weight material puts less strain on the roofing structure.
Can metal roofing be installed over my existing roof?
Because of its lightweight properties, metal roofing can be installed over an existing roof. However, many roofing contractors prefer to tear off the old roofing material to ensure the proper sheathing and insulation is installed. This helps optimize the performance of the new metal roof, and it can help extend its lifespan.