The answer to 'air duct sealing installation cost' is that the cost can vary widely depending on several factors. Typically, the cost for professional air duct sealing installation ranges from a few hundred dollars to several thousand, depending on the size of your home, the complexity of the ductwork, and the extent of the sealing required.
Some key factors that influence the cost include the accessibility of the ductwork, the materials needed (such as sealants, mastic, or foil tape), the number of vents or registers, and any necessary repairs or modifications to the ductwork. The cost is also affected by your location and the rates charged by local HVAC contractors.