US Patent 7222645 Duct insulation having condensate wicking

An insulated duct-wrap insulating product for an air duct that incorporates a wicking media to transport condensed water on the duct surface to be evaporated into the atmosphere. A wicking fabric, or fibrous media, incorporated as part of the insulating duct wrap is in contact with the metal air duct surface. A portion of the wicking fabric extends into the interior of the air duct, typically through joints in the duct system. When water vapor condenses on the air duct surface it is transported by the wicking fabric and evaporated from the wick surface within the air stream being transported by the ducting system.