I know that just about everyone has heard about companies that clean the air ducts in homes. The typical way to clean the air ducts is to place a round bristle brush about the same inside diameter as the pipe. It is either pushed or pulled through the pipe. Many times it also has a vacuum suction as part of the brush. Then after they have cleaned the duct they come back and spray various anti-bacterial and anti-fungal chemicals to aid in the cleaning of the ducts.
Is it a good idea or is it a bad idea to clean your air ducts?
It depends on what the air ducts are made of! If you have the strong sheet metal air ducts, then it might be a good idea to have a qualified company clean them. The key is a quality company that knows what they are doing!
But, if you have those flexible plastic air ducts that are in the majority of the homes that have been built in the past eight or so years then you might want to rethink having them cleaned. The flex-duct type plastic air ducting is like a sandwich. it is comprised of an inner layer of plastic like sheeting then a layer of fiberglass insulation and then an exterior layer of plastic. Most of the time the inner layer has a wire that is built into it so that the duct will have additional strength and flexibility to help keep the duct from crushing and closing up. This wire also gives the air duct a fan or accordion shape, that traps dirt and dust. The plastic flex- duct can not effectively be cleaned. Most of the time if cleaning is attempted the flex-duct will be damaged
We also have fiberglass fiberboard air ducts. This type of air duct can not be cleaned either. The fiberboard has a protective covering that is easily damaged.
We really do not want fiberglass particles floating around in the air we are breathing every day!
This is a picture of a damaged duct as see from a floor register on a new construction home that I inspected. This is the result of an air duct cleaning company cleaning the construction debris out of the air supply ducts. The pink is the fiberglass insulation part of the flex-duct:
So, if you have metal air ducts you can clean them. If you have flexible type of fiberboard air ducts you should not clean them. This type of air duct needs to be replaced and not cleaned.
Scott Patterson has been a professional home inspector since 1995 and works out of the Greater Nashville TN area. You can contact him at his office 615-302-1113 or on his cell at 615-870-4162 via text or voice.