One of the major concerns many homeowners have when considering metal roofing is the internal temperature of their home, particularly that of their attic space. It’s rumored that, because metal is a conductor of heat, it must ultimately result in a hotter house during the summer months. The logic is reasonable, albeit flawed. People tend to believe that because metal objects that have been left out in the sun are hot to the touch, this automatically translates to a metal roof creating an overly hot attic space and home below it.
This is one patently false rumor. The truth is that metal roofing doesn’t increase the internal temperature of a home and can even help regulate a home’s temperature by making it cooler in the summer months.
Metal Roofs Make Homes No Hotter Than Any Other Roof
No roofing system will create a cool home in the summer, but most roofs help to keep out heat that comes from direct sunlight. While it is true that metal roofs will absorb heat, some of which can be transferred into an attic living space below, this is no different than any other roof. Any dark-colored material, including asphalt shingles, ceramic tiles, wood, etc., will absorb heat when exposed to direct sunlight for prolonged periods. Metal roofing is no different.
How Metal Roofs Help Cool Houses
Unlike other roofing materials, metal roofing has properties that can help cool the surface and interior temperatures of a home.
- Materials with more weight and mass retain heat longer. Metal roofing is one of the lightest and least dense roofing materials options, meaning it will cool down more quickly once the sun goes down.
- Metal has a low thermal mass and reflects light, which means less heat will be absorbed throughout the day.
- Lighter colors reflect, not absorb heat. Since metal roofs can be painted in any color, unlike other roofing materials, you can choose a metal roof with a lighter color to keep temperatures down.
What Affects Home Temperatures Most
While the color and type of roofing material you choose can help, it’s ultimately the type of construction and the insulation and ventilation below the roof that are the largest determinants of how cool a home stays. If you are looking to make a difference in the temperature in your home, begin with your attic insulation and ventilation, or check the age and state of your windows (old windows are leaky and will allow cool air to escape your home).