Our house is only seven years old, built in 1995.
We have a floor drain with a metal screen cap. We are told by our plumber that it is a "P" trap or drain. We are supposed to pour some water into this pipe every one or two weeks. If the water dries up an odour emanates from this pipe. The smell is sewer-like and I would like to stop it from coming into our basement on a more permanent basis. Presently I pour some water with a little Javex into the pipe (drain) to remove the odour. It returns in a matter of hours or a few days. What can I do to stop this from occurring?? Is there something I can add that will not evaporate that will stop the smell from escaping, or is it a job for a plumber??