Roof Weight
Traditional shingle, tile, and slate roofs can weigh from 2.75 to as much as 20 pounds per square foot. While homes have been designed to handle roof weight, as structures age, these heavy roofs can cause cracks and shifting and, in worst cases, even structural collapse. A metal roof, though, usually weighs less than a pound per square foot. This can be very beneficial to aging structures. An additional benefit is that some metal roofs can even be installed over existing shingles avoiding the expense and landfill disposal of removing the sold roof.