Help with smelly toilet

[MassiveJim]

our ensuite bathroom and main bathroom share the same soil pipe.
when i go for a wee first thing in the morning in the ensuite there is a strong sewer smell, when flushed it seems to go away.

I thought this could be down to the vent pipe having a durgo valve on it so not allowing gases to escape properly.
So last week I had a builder come and install a vent tile and the stack is now connected to that, so it is now vented to open air.

However it hasn't solved the smell issue with the ensuite toilet.


any ideas

 

[MassiveJim]

Have you checked for any leaks from the soil pipe. I know our ensuite has a very small leak that's more noticable in the winter months when the window is shut

Its all completely boxed in, on the 1st floor it is hidden behind a false wall.
The top of the wall is open in the loft though, so if there were any leak I would most likely be able to smell it in the loft. (have smelt smells up there before we replaced the 20 year old durgo valve)


the smell is only "released" when I "break water" so I can't see it being a seal otherwise I would assume that there would be a smell there anyway.
Also the fact that it goes completely when the toilet is flushed.