Leaks where waste pipes connect to soil stack

[houstonwehaveaproblem]

I have a horizontal soil pipe which is boxed in.

I have noticed the plasterboard is staining in three locations along the boxing. There are three waste pipes attached to the soil stack in similar locations to where the stains have appeared. Soil pipe was fitted about 5 years ago.

From what I can remember the waste pipes enter the soilstack through push fit rubber grommets.

Seems odd that all three could be causing a leak.

Any ideas or advice before I take the plasterboard box section down after Xmas.

 

[SandyLyon]

Need to expose first to find out if they have used “strap on“ bosses or bossed socket’s and see exactly where the leak is coming from.

 

[houstonwehaveaproblem]

They are rubber push fit type. I can remember seeing them when they were fitted

 

[SandyLyon]

They are rubber push fit type. I can remember seeing them when they were fitted

Yes, but are they fitted into a bossed pipe or a strap on boss.

If a strap on boss it should be installed with gap sealing adhesive to completely seal the strap to the soil pipe.

 

[houstonwehaveaproblem]

I'm pretty sure the are inserted into the outlets on the soil stack if that makes sense