Metal roofs can last up to 100 years, with some manufacturers providing 50-year warranties. Because of their longevity, most metal roofs are less expensive than asphalt shingles in the long term. Metal roofing can consist of a high percentage of recycled material and is 100% recyclable. It does not get as hot as asphalt shingles and it reflects heat away from the building underneath in summertime. On a larger scale, its use reduces the heat island effect of cities when compared to asphalt shingles. When installed over a strapping system between the plywood and “cool-color” metal on top,which provides an air gap between the plywood roof sheathing and the metal. Cool-color metals are light, reflective colors, like white.