The GAF coverage period for materials, parts, and labor defects is 50 years non-prorated and applies exclusively to single family detached residences. For all other structures, the coverage period is 20 years, non-prorated. Enhanced warranties are only available through GAF certified contractors. Be sure to verify that your roofing professional holds the proper certification. Acres Roofing ensures exceptional quality by conducting a thorough roof inspection upon the completion of every project.