The answer to 'average cost for air duct sealing' is that the typical range for professional duct sealing can vary widely, but generally falls between $500 to $2,000 or more. The cost is influenced by factors like the size of your home, the accessibility and condition of the ductwork, the materials and sealants used, and the complexity of the job.
For example, sealing a small, easily accessible duct system in a single-story home may cost on the lower end, while a larger, multi-story home with extensive ductwork in tight spaces could be on the higher end. Additionally, the type of sealant used, whether mastic or foil-backed tape, can also impact the overall price.