Metal aka the “forever roof” can be an excellent choice for residential re-roofing applications, particularly in comparison to the less-durable, temporary roof types such as asphalt shingles.
Pros of Metal
Extremely Durable and Long-Lasting
Compared to the more traditional asphalt shingle, metal is a far more durable and longer-lasting option for residential roofs.
In fact, most homeowners who choose to install a metal roof on their home will never have to think about re-roofing again. Why not? Well, metal roofs are proven to last two to three times longer than asphalt, with 50 to 60 years lifespan for higher-end Kynar 500 coated metal roofs such as field-locked standing seam and aluminum shingles. A roof made of zinc or copper can last well over 100 years.
A metal roof can withstand the elements for far longer than an asphalt roof. Sun or rain, snow or ice, a metal roof will remain attractive and weatherproof for a very long time.
Moss- and Fungus-Proof
Unlike asphalt, metal roofing is 100% unaffected by the growth of moss, mold and mildew, fungus and moss — all the common afflictions known to plaque impermanent roofs made of asphalt or wood such as cedar shingles and shakes.
Did you know? Moss and fungus growth not only look extremely undesirable, but they can also dramatically shorten the lifespan of an asphalt roof. — In fact, without ongoing maintenance and sealing and/or regular roof cleaning, significant moss outgrowth can cut the “already short lifespan” of wood and asphalt by almost half! This is exactly the kind of contrast that makes metal the perfect choice for areas that are particularly prone to moss growth, such as heavily wooded environments.
Raccoons, Rodents, Pests, and Wild Animals Proof
If you live in a heavily wooded area, where raccoons and rodents can get onto your roof from the tree branch, you can rest assured that they won’t be able to damage a metal roof to break into your attic.
Did you know? There are many reported cases of pests and wild animals breaking away the asphalt shingles, destroying plywood, and getting inside the homes to cause further damage.
Fire Retardant Material
Another benefit of a high-end metal roof is that metal is a fire-retardant material. Most high-end metal roofs come with Class A fire retardancy rating. This can be a particularly important benefit for homeowners who live in areas that are prone to wildfires.
Metal roofs can also be useful in locations that experience other types of extreme weather, such Kansas, Oklahoma, and other areas where hail storms are common.
Sustainability of Metal
Metal is a sustainable and durable alternative to asphalt or cedar. Metal roofs can last at least three times as long as asphalt shingles, without requiring as much maintenance.
At least 30 percent of the material that is used to create a metal roof has been previously recycled. Some metal roofs are made of 100 percent recycled content. — This, coupled with the superior durability and long lifespan, makes metal an environmentally friendly roofing option.
All metal roofs can be fully recycled at the end of their service life.
Metal offers yet another important advantage over other materials; Metal roofs can stay much cooler than their asphalt counterparts on a hot sunny day, helping to regulate the temperature inside the building, while also reducing the demand for electricity and AC load.
How can a metal roof help keep my home cool in summer?
Metal coated with a Kynar 500 based resin can achieve solar reflectance index (SRI) ratings of over 70. Compare that to the SRI of only 20 to 25 for Cool Roof (CRRC) rated asphalt roofs.
Reflecting away most of the solar radiant heat can help keep the roof surface significantly cooler, thus limiting the amount of heat that can be absorbed and transferred inside the house.
Metal also has good thermal emissivity, which means that whatever solar radiant heat was observed during the day, will be quickly released back into the atmosphere with the sunset.
Did you know? Even the most energy-efficient metal roofs will absorb some of the heat from the sun during the day, but unlike asphalt, they will also quickly release it during the unset of the night.
Metal cools much faster than asphalt. In a hot environment, a metal roof can help keep the house significantly cooler by reflecting solar radiation and any accumulated excess heat back into the atmosphere.
Thus, metal reflects a significant amount of solar radiant heat during the day, without transferring much of it into the house, while any heat absorbed is quickly released during the night.
Note that a properly insulated and ventilated attic space is the key to a well-functioning and energy-efficient roof and a more durable, healthier, and comfortable home.
Good for All Seasons and Climates
Metal roofs can help to keep your home cool during the hot weather, but they can also provide important benefits in a cold environment. Ice dams are a significant problem for many homeowners in the United States and in Canada.
Did you know? An ice dam can create a leak in a roof, but it can do so surreptitiously, so that a homeowner is not aware of the problem for many months!
Ice dams occur when there is a combination of insufficient insulation under the roof, in the attic space, and poor ventilation in the roof.
The lack of adequate attic insulation means that hot air can rise through the house, into the attic space, where it could become trapped under the roof deck (often to poor venting of the attic space. — This trapped heat gradually warms the roof deck and melts the snow that is lying on top of it.
The resulting melted water begins to run down the roof slope, refreezing along the cooler eaves, where the ice forms an ice dam.
An ice dam is a wall of ice which builds up along the eaves of a roof. As more snow is melted, it runs down towards the eaves and adds to the wall of ice.
Once there is enough ice along the eaves, the water will begin to be trapped. It will be unable to run off the roof, and it will instead be pushed back under the roof shingles, where it may leak into the house. — All of this can be avoided by installing a metal roof.
Metal roofs can help prevent snow and ice from accumulating on the roof, which means that ice dams are unable to form.
A metal roof is one of the ways in which ice dams can be effectively mitigated and prevented from forming in the first place, so they are an ideal choice for cold climates.
Disadvantages
Despite all the benefits, there is one important disadvantage to choosing a metal roof, and that is the higher initial upfront cost of investment.
Many homeowners may be cautious about buying a metal roof because the initial upfront cost will be higher than choosing a more conventional option such as asphalt shingles. — This makes sense, if you are buying a roof for a house or building in which you only have short-term (5 years or less) plans of staying in.
If you will not be there to take on the cost of replacing the asphalt roof in ten or fifteen years, then asphalt will be the cheaper option.
Total life-cycle cost caveat: However, if you have long plans of living at your house, then it is worth comparing the cost of a metal shingle roof to the cumulative total cost of all the asphalt roof replacements you will likely need to pay for during your residence at the property.
In addition to the above, there are other important benefits of having a metal roof including its unique attractive appearance that can help enhance the curb appeal of a house, coupled with metal’s ability to keep your home cooler in the summer, while helping minimize and prevent heavy snow build-up and ice dam issues during winter, especially if you live in the snow country.
A metal roof can also help reduce the cost of your homeowner’s insurance premiums thanks to its superior durability, longevity, and fire-retardant properties and ratings.
Some homeowner’s insurance companies can provide 30% to 35% discount on homeowner’s homeowner’s insurance policies for homes protected by a qualified metal roofing system.
Finally, your peace of mind with respect to the roof protecting your home and your family is hard to put a price tag on. Knowing that your roofing system is designed to provide a durable, long-lasting, and weatherproof protection for your home and your family is an important intangible, especially if you happen to live in a storm-prone and/or fire-prone area.
Verdict: a metal roof will likely prove to be the most cost-effective roofing choice when viewed over a long-enough timeframe and through a lens of a long-term investment in the roof’s durability and longevity, improving the home’s overall curb appeal, and benefiting financially from the greatly improved energy efficiency of a metal roof.