Ductwork repair service call. Went through full video ductwork inspection. Duct work is transite with metal connectors. Bathroom duct had water sitting with odor. Sewer flies were present in the house. All connections were in good condition except in the bathroom. Looked in the basement and TV'd sewer. 4" cast, got back to the stack. Toilets and kitchen line all tye in underground. Will quote to descale cast from outside c/o to stack. They will have a plumber put a c/o on 2" line. We will then clean and TV that line. Will give an estimate for the ducts as well.