Patent ID: 8851125

Claim:
An intermediate insulating ductwork product comprising a planar insulating layer having a protective layer on an innermost surface thereof and a plurality of parallel channels comprising cross-sections with tapered sides formed in, the innermost surface such that the protective layer is cut when the channels are formed; a vapor proof layer comprising an adhesive that secures the vapor proof layer to the protective layer applied to the innermost surface and the channels such that the vapor proof layer bridges the plurality of parallel channels; and wherein, with subsequent mechanical manipulation, the intermediate insulating ductwork product can be bent in regions adjacent bottom portions of the channels, thereby causing the channels to substantially close to form a non-planar, derivative insulated duct without metal ductwork having an inner throughbore and the vapor proof layer forms an innermost vapor proof lining to the inner throughbore of the derivative insulated duct and a surface of the intermediate insulated ductwork product opposite the innermost surface forms an outermost surface of the derivative insulated duct that is in contact with an external environment; wherein the vapor proof layer comprises a sealing means to substantially seal the inner throughbore with respect to an outer circumference of the derivative insulated duct.