The answer to 'average cost of air duct' is that the typical range for air duct cleaning can vary significantly, but generally falls between $300 to $700 for a standard-sized home. The cost is influenced by factors such as the size of the home, the number of vents and ductwork, the level of contamination, and the accessibility of the ducts.
It's important to note that getting local quotes from reputable air duct cleaning companies is essential, as prices can fluctuate based on your geographical location and the specific needs of your home. While some homeowners may be tempted to tackle this task themselves, it's generally recommended to hire a professional for a thorough and safe cleaning.