When installing new shingles on a residential dwelling a home owner should not have the shingles layered more than once onto the original shingles. This means when a homeowner replaces a roof on a home with a maximum of two shingle layers, the existing shingles will need to be removed before installing new shingles. Both the FHA, We are a full service roofing contractor specializing in roofing tear offs. If you need immediate service or free quote on a new roof installations, call (937)726-2868 for more information. A roofing professional is standing by to help you.