We had our ducts cleaned by another company about 30 years ago, but nothing since. Our HVAC technician recommended Advanced Air Duct Cleaning especially since we had construction done on our kitchen and bathroom last year. Our air duct technicians were Andy and Cory and they did such a great job. They even had two dogs and two cats to deal with. It took about 3-1/2 hours to complete the job. They took before and after photos and in the after photos the duct work looked shiny and new. Plus, they used an antimicrobial spray in the ducts which had a nice, subtle scent. We are very pleased with the work they did and recommend calling them. You'll be happy you did!