The main plumbing pipe leaving my house has a joint where it goes off and over (sort of like a curved T valve) but the end is covered with duct tape. This is not the clean out valve but it is near this joint. We recently finished out our unfinished basement had a bathroom installed in the next to where this pipe is located. This pipe is now located in a long storage area mostly closed off except for slatted louvor doors. I am not sure the bathroom was properly vented because we have begun to smell smells. I do know the plumber did not run a pipe to the roof. Should I be concerned about the duct tape over the pipe? I have investigated the smell and have been told we need to install an aav valve.

The new plumbing fixtures should be vented somehow. Venting into the living space does not meet code. Did your plumber perform the work under a building permit? If he did, it should have been inspected by the city or town inspector and the lack of venting would have been noticed. Was the pipe with the duct tape installed as part of your bathroom work or did it exist before the work was done?

The duct tape covered pipe was there when we bought the house. We didn't have to have permit for building inside a structure. We discovered that when we (my husband and I) put a bedroom in the basement.