Awful smell

[Eileenb]

We moved into our house a year ago after it had had a new bathroom fitted by the owners. From time to time we get a really bad sewer smell in this room which contains a shower unit, a bath, a washbasin and a toilet. In the beginning we just ran the water in the shower, washbasin and bath, fearing there was no water in the U bends or that it had been siphoned out somehow. Is this possibly the cause. Either way, the smell returns regularly.

It doesn't seem to be weather related or how often the room is used. My husband has had the bath panel off and looked into various other places but can't see anything untoward and there are no apparent leaks.

When we moved in we realised that the cistern was filling with hot water so the previous plumber certainly didn't appear to know what he was doing. We called someone in to rectify this.

Help please, are we missing something obvious? :38:

 

[JCplumb]

First thought is that you may have basin/shower/bath plumbed directly into the soil pipe from your loo.
If this is the case water may be getting sucked out of traps when the toilet is flushed, or they may just be evaporating and allowing foul air to pass.
Check your waste pipes to see if they branch directly off your soil pipe, if they are you could try anti-vac traps or Hepvo traps as a solution.

 

[Eileenb]

Thank you so much. Apparently the sink shares the same pipe as the toilet so a trap seems a likely solution.

 

[Elforleather]

Does your soil pipe vent outside? I was wondering if your stack was inside and that someone may have decided to tidy the place up a bit and cut it off and placed a Durgo valve (Stub Stack) on it for venting? They can stick at times and this would allow a smelly build up. Problems occur if there is no other vent on the system.

 

[Eileenb]

Does your soil pipe vent outside? I was wondering if your stack was inside and that someone may have decided to tidy the place up a bit and cut it off and placed a Durgo valve (Stub Stack) on it for venting? They can stick at times and this would allow a smelly build up. Problems occur if there is no other vent on the system.

No, it is on the outside

 

[WHPES]

Quick fix would probably be an anti siphon trap on the sink, else do the job properly and join the sink to the stack as it should be.

Had to deal with a similar situation last year. When the toilet was flushed, dirty water flowed into the bath!

 

[thompsonbrown]

good advice about anti siphon trap but also check the wc. if its a older suite he could have connected the overflow to the soil pipe ive seen this done a few times where they make a small trap using overflow elbows and fill with water. but when the water in the trap evaporates the smells from the waste pipe come back