Plumbing – Bad smell from bathroom – plumbing

bathroomplumbingsmell

I'm living in a building of 6 floors, I'm at the 5th floor.
I made a full renovation to my apartment about 8 years.
Recently I began smelling a bad sewage smell from the bathroom (from drainage hole).

The thing I can't understand is how it's possible if I have a siphon that always keeps a high level of water such that it blocks the passageway of air…

It's driving me crazy and I don't know how to solve this issue.

Would appreciate a lot your advices,

Best Answer

The thing I can't understand is how it's possible if I have a siphon that always keeps a high level of water such that it blocks the passageway of air...

If the building vent gets clogged, then waste falling through the common downpipe can suck water out of your U-bends/P-traps.

The solution is one of

Also, If you leave a sink/bath/shower unused for a month, the trap can dry-out by evaporation. This is mostly solved by pouring a litre of water down the unused sink/bath/shower once every few weeks. I read that some people add a layer of oil (maybe a tiny quantity of vegetable or mineral oil) to slow down evaporation.


Linked examples for illustration only, seek local equivalents.