I have a bad smell in the bathroom, sewer like smell. Just moved in, but pretty sure that the bath, the separate shower and washbasin all lead into the same pipe, which descends into the cellar and joins the waste pipe from kitchen and then I presume the WC.
There's no p-trap under the wash basin just a small trap for waste but without resting water blocking gas. I presume same for shower, for the bath, don't have easy access so can't see.
I do have good access in the cellar so I wondered if it's possible to put a p-trap there as a catch all for any backup gases but that doesn't appear to be given on the net asa solution so asked myself why not?
Any advice would be appreciated.