Sewage smells in bathroom of 2nd (top) floor flat in Leeds, UK

[agemogolk]

We have various smells - usually sewage - coming from our bathroom occasionally. Sometimes every day then nothing for a week or two. It's a second/top floor flat and the smells come from the main bathroom wihch shares the soil pipe with floors below. We have checked all of the traps (sink, bath, toilet) and the seals on the toilet soil pipe. There is MVHR extract fan running constantly. The nighbours in flats below have not had any issues. Apparently this has been happening since the flat was built in 2011. When a plumber was around for another job it was mentioned, but at the time there was no smell.

Could there be a problem with vent or soil pipe? Is there a test that can be done? Smoke/camera?

We are in the south Leeds Hunslet area. If you think you can help please get in touch.

 

[exedon2]

Picture of bath and basin trap would be useful I've seen bath trap seals sucked out by momentum in past.

 

[oz-plumber]

It sounds like a sewer vent has been forgotten about during the initial installation.

Smoke test first and then maybe camera test.

Good Luck!!

 

[townfanjon]

Do you have an internal or external soil stack ?

 

[agemogolk]

Picture of bath and basin trap would be useful I've seen bath trap seals sucked out by momentum in past.

I'll get some photos. I did check that the bath trap wasn't being sucked out after washing machine or dishwasher had drained - seemed OK. It gets used regularly so isn't left to evaporate. The basin trap is one of those inline membrane types - use doesn't seem to correlate with smells.
It will be fine in the morning - in fact never seems to smell in the morning - and when returning from work the smell will sometimes be present. It's not always the same smells either (but never nice...).

 

[agemogolk]

Do you have an internal or external soil stack ?

There are two soil stacks in the flat. Both internal - one in the corner of bathroom and other in corner of ensuite. Both boxed in etc.

 

[agemogolk]

It sounds like a sewer vent has been forgotten about during the initial installation.

Smoke test first and then maybe camera test.

Good Luck!!

Where would that vent be? Would it affect the flats below or is the top floor where the gas would vent? Should it not go out some kind of vent at the top of the pipe? Is it easy to do a smoke test? Any idea who can do these and how much it might cost?

 

[townfanjon]

There are two soil stacks in the flat. Both internal - one in the corner of bathroom and other in corner of ensuite. Both boxed in etc.

On top of the stacks you will have AAV ‘ s , ( air admittance valves) you potentially have a faulty one .

 

[agemogolk]

On top of the stacks you will have AAV ‘ s , ( air admittance valves) you potentially have a faulty one .

Is there a way to test if this AAV is faulty if you don't have access to it?

 

[Stu-B]

Won’t this be a landlord thing and why you pay building rent?

 

[townfanjon]

Is there a way to test if this AAV is faulty if you don't have access to it?

No not really , the only thing you can do is drill a hole or two and use your nose .

 

[agemogolk]

Won’t this be a landlord thing and why you pay building rent?

Hopefully it is - i'm looking into that. Would like to be aware of the issues and possible solutions before I get involved with management company.

 

[agemogolk]

Won’t this be a landlord thing and why you pay building rent?

So we had the building maintenance contractors around to have a look. They said these buildings have no AAV and the soil stacks are vented through the roof. They checked the floor level manifold and declared it to be sound. They checked the bath trap and pipe work - all good.

They said the pan connector is on at an angle and shouldn't be installed like this and is possible entry point if top is not sealed correctly. Also, they recommended replacing the "HepV0" dry trap under the sink with a proper water trap. Apparently the dry trap is only supposed to be used for horizontal runs or rarely used condensate drains.

Got a second opinion from a plumber who came to have a look as requested by another contact and he reckoned it's probably the sink trap and wasn't concerned at all about the pan connector (wasn't a confidence inspiring tradesman though...).

 

[agemogolk]

Picture of bath and basin trap would be useful I've seen bath trap seals sucked out by momentum in past.

I've checked the bath trap when flushing etc. The water wobbles a bit, but doesn't get sucked out. Never seems to be lower than it should be. Attached pics of the sink trap and the pan connector.

 

[ShaunCorbs]

Gaffa tape up the basin overflow and waste if the smell goes away you’ve found your issue

 

[agemogolk]

Gaffa tape up the basin overflow and waste if the smell goes away you’ve found your issue

Thank you - will do that right now.

 

[agemogolk]

Thank you - will do that right now.

So i sealed up the sink hole plus overflow with duck tape earlier and the smells came in over the last hour. I've now tried to seal the top of the pan connector with tape.....