Internal soil stack leak?

[Converse2020]

Hi,

I'm after some advice on how to proceed.

7 year old house. 2 bathrooms upstairs and loo downstairs.
Soil stack from ensuite is internal and boxed in. There is a leak at the bottom of the boxing on the ground floor.

How do I proceed ? Take out plaster board boxing ? - but of course svp could be leaking from top.

The boxing goes to the ceiling in the ensuite but there is no vent pipe through the roof (the 2nd bathroom has an external svp).

Have seen suggestions for pipe test. Is this straight forward for a plumber ? Should I just call my house insurance company ?

Thanks

 

[denso13]

Take out plaster board boxing ?

Unfortunately yes. It might take a few holes to identify where it is leaking but you'll have to start somewhere.

 

[Hugh Jaleak]

Only solution is to get to the pipework and look. Test will tell you it is leaking, wont tell you where though. I'd start though where the bathroom connects, most likely a boss joint that's come adrift. Highly unlikely to be leaking above any connections, so I would start on the en-suite connections and work down if necessary.