Can a Metal Roof Be Installed Over an Existing Asphalt Shingle Roof?

Metal roofing only weighs a third of traditional roofing, so in most cases you can install a metal roof directly over your old roof.   A proper underlayment or structure should be used to isolate the panels from the asphalt shingle surface. Roofing over your old roof can save a great deal on labor by not having to strip your old roof, and save landfill dump fees by eliminating these wastes.  There are a number of ways to roof over your old shingles, so it’s recommended to consult with a reputable roofer.  If the roof structure is questionable, or there are three layers of shingles, stripping and repairing the structure will be required.