You can expect anywhere from 1.5 to 3.5 hours for an average size home and longer for larger homes. We realize that is a pretty wide range but there a few factors involved like degree of contamination, crew size (a 2 man crew will accomplish more in less time), and the complexity of the duct system. Please note, the time we spend in your home is devoted to cleaning your air ducts. That is to say, some companies will state they take the time to do it right, but the majority of that time is spent washing your vents by hand with very little time spent actually cleaning your ducts, or just standing around banging on the ducts a couple of times while they tell you that the vacuum is doing all the work, or any of the other time wasting gimmicks used by unscrupulous duct cleaners. Our expertise and the money you’re paying us is all spent on the thorough cleaning of your ventilation system.