Running branch to internal soil stack - externally

[rikdogguk]

I’m planning to remodel my bathroom and fit an en-suite in the adjoining bedroom.

The soil stack currently runs internally down the inside corner of the house in the bathroom upstairs and cloakroom toilet downstairs.

I’d like to avoid running waste for the new en suite internally if possible.

one option is to move the internal soil stack to the outside of the wall. This will necessitate work to the drains to connect up.

I’m wondering if a simpler solution is to run a branch externally and bring it back through the wall to connect to the internal stack, via a 90 degree bend and branch connector. Is this allowable under building regs? I’d like to avoid digging up the drains for a new connection if at all possible!

Thanks

RD

 

[ree]

OP,
Could you post a rough sketch plan view of the existing bathroom, and a plan view of the proposed bathroom? Plus a pic of the outside elevation showing any gullies?

 

[Hugh Jaleak]

Should be allowable, how easy though is another matter, breaking into existing stack may prove a bit of a challenge.

Main consideration will be, the Fall on the new section, how far away from the existing stack is the proposed new WC position?

 

[rikdogguk]

T

Should be allowable, how easy though is another matter, breaking into existing stack may prove a bit of a challenge.

Main consideration will be, the Fall on the new section, how far away from the existing stack is the proposed new WC position?

The existing wc is 2.2m from the stack. It is connected via a boxed in soil pipe branch which runs under the bath. The new wc will be around 3.6 m from the stack (the other side of an internal wall but against the same external wall).

I was thinking of doing the break in at ceiling height in the cloak room underneath. This would give me more than enough fall (may be too much?). I was planning to break in by removing a section of pipe and fitting junction using rubber slip coupling if needed.

 

[Hugh Jaleak]

It sounds feasible but a bit of a Heath Robinson affair. If existing stack is plastic, then use plastic couplings, I'd be very wary of using Fernco type couplings internally personally. Fall wise, should be ok, too much is better than not enough in these situations.

Given the proximity to the existing drainage, a new external stack and appropriate connection to drain underground would still be the better option, by a country mile though.