As metal roofing grows in popularity for use on homes, many people have questions about how it performs. There are also many common misconceptions, or metal roofing myths. The Metal Roofing Alliance, a nonprofit educational organization, answers many of these questions below.
Lightning: Does installing a metal roof make your home more prone to lightning strikes?
Lightning occurs from the highest object in an area, regardless of the material from which it is made. Metal roofing does not create nor attract lightning and poses no additional lightning risk to the structures it protects
Hail: How does a metal roof stand up to hail?
Quality metal roofs are naturally very tough and highly resistant to hail damage. Hail will not penetrate a metal roof. In fact, many metal roofing products have the highest impact resistance and hail rating granted by Underwriters’ Laboratory (UL), a leading product safety testing and certification organization.
The majority of metal roofing earns a UL2218 Class 4 rating, meaning that a sample of the product did not crack when hit twice in the same spot by a 2-inch steel ball, which, in a storm, would translate into a huge hailstone.
As a result of metal roofing’s superior performance in hail prone areas, some insurance companies even provide a reduced rate for homes protected by metal roofs.
Noise: Is a metal roof loud during the rain? No.
The concern about the noise of hard rain on a metal roof is usually related to memories of rain on barns or patio awnings, when there’s nothing between the person and the roof but air.
Modern metal roofs designed for use on homes are part of an overall roofing system. They are installed with underlayments and in the case of re-roofing, a metal roof is often added on top of several layers of asphalt shingles. These multiple layers, plus the roof decking, insulation and attic space dampen the sound, making a metal roof no louder than any other modern roof.
In fact, metal roofing owners often report they hear more noise from a skylight than the roof. Our members also tell us that some homeowners are disappointed at how quiet their roof is, wishing for the “white noise” of rain on the roof. Luckily, there are apps that can provide the sound if you like it.
Heat : Won’t a metal roof retain heat, creating higher energy bills? In fact, NO, the opposite is true.
New technologies allow even darker colored metal roofs to absorb less heat through the use of highly reflective pigments that reflect solar energy. Most homeowners who install metal roofs will see a reduction in their energy use.
For example, a study conducted by Oak Ridge National Laboratory found that installation of a reflective metal roof can save homeowners up to forty percent in summer cooling costs. Highly reflective metal roofing panels are created with special pigment paints that reflect the sun’s’ energy in the infrared spectrum thus reducing the heat load transferred to the interior of the structure.
Rust: Do residential metal roofs rust? No.
Driving along a country road, you may have seen rusty metal roofs that my cause you to pause when considering a metal roof. It’s important to remember that the type of roofs placed on barns are far different than today’s quality metal roofs that are designed for use on homes.
All modern steel roofing has a protective barrier on both sides of the sheet called a metallic coating which protects against rusting. This is underneath and separate from any paint which imparts color to the product. There are two types of metallic coatings used Galvanized and Galvalume.