Help with Bathroom Soil Pipe in En-suite Drainage and wastage systems and plumbing help, advice and answers

[RichGM]

Hi all, am re-furbing an en-suite and would like to turn the WC 90 degrees. This means drilling a new hole through the external wall to connect the new soil pipe to the stack.

As luck would have it (or so I thought) the new WC soil pipe will pop out pretty much bang on in line with the stack.

But that is also the problem. The soil stack sits only 35mm away from the wall but all the Y branch joints I can find protrude at least 100mm from the stack meaning the joint connecting the new WC waste to the Y branch would be inside the brickwork.
Though I can't find any specific rules on this my instinct says that you shouldn't have such a joint buried in the wall as if it leaks it would be leaking into the cavity etc..

I'm better with woodwork than plumbing so hoping someone will
a) understand what I'm banging on about and
b) point out I'm missing something blindingly obvious and be able to offer a solution!

Have attached pics and a drawing of proposed change to soil pipe layout.
Cheers Rich

Existing WC - new WC to be rotated 90 deg to this one

Existing soil pipe exit

Drawing showing rotated branch to proposed new WC soil pipe

External view of existing soil pipes

[stoneyboy]

Hi richgm
Modern plastic soil pipe joints are pretty reliable but suggest you fit a new T to replace the existing one.
Regards S

[RichGM]

Thanks S, so if I put on a fresh fitting it'll likely be ok even though the joint will be buried part way through the wall?

My instinct says it'll be fine but unsure what the 'pros' do these days!
Thought there may have been a special fitting or method in these cases.

I'll crack on...

Cheers
Rich

[stoneyboy]

Hi richgm
The pipe coming into the T will be going downhill coupled with the integral rubber seal there should not be any issues. Use a ringseal T.
Regards S