We get asked regularly if a metal roof will make a home hotter in the heat of the summer. The answer is, probably not!
Energy Star Certified
Just about every one of the finished steel and aluminum products we sell offers “Energy Star” finishes, which are formulated to reflect sunlight and minimize heat absorption and fading of the roof's color. These coatings significantly reduce the temperature that the roof can reach when the sun is beating down. Still, on a very hot day, ANY roof that is directly in the sun is going to get quite hot, reflective coating or not. Compared to asphalt shingles, though, the metal roofs won’t be any hotter - and usually cooler.
Understanding Air Space
Interestingly, it's actually not the temperature of the roof itself that will affect comfort in your home. It's what's beneath it. The amount of heat that the roof covering conducts into the attic below is far more significant. And it's in this scenario that metal roofs really separate themselves from asphalt shingles (and most other roofs types). That's because our shingles, shakes, and metal diamonds feature not only reflective coatings, but also (and more importantly) air spaces between the metal roof and the roof deck. This airspace dramatically reduces heat conduction to the deck beneath, which in turn reduces heat build up in the attic. This lower heat conduction into the building itself is what can dramatically reduce energy costs and increase summer comfort in a home.
A final big plus to metal roofs in the hot weather is the fact that they hold the least amount of heat after the sun goes down. A metal roof is very, very light compared to most other roofs and this low thermal density means the meal will be cooled to ambient temperature quickly after the sun goes away. Heavier, denser roof materials like asphalt and concrete can’t compare.
A very hot summer day will be a very hot summer day regardless of what roof you have, and a metal roof won’t “air condition” a building all by itself, but it can certainly reduce the energy load.
For more information about this or your roofing project, contact us today.