Hi,

Soil stack in main bathroom sits the other side of a stud wall to a planned en-suite. Stack has a 92.5 deg branch going off to the loo, and at 90 deg at the same level, the 43mm waste from the bath.

At the same exact point I would need to join the stack in height terms, I would like to join the waste from the en-suite shower. However, of the two stack bosses remaining at that section, I'd have an opposing waste situation - either opposing the WC (obviously bad), and the other, would be opposing the bath waste from the main bathroom. There isn't room for a manifold waste. Any suggestions on what I could do? I'll try and sketch in letters, the view from above:


-O stack
!!
!!
WC

The ensuite shower would need to join from the direction of the word stack, opposing the bath waste indicated by the - but I think that's not permitted?

You can join into the boss opposite the wc or bath waste it don't fall into what is known as the danger zone.

Thanks - Perhaps I'm misreading the regs - the boss opposite the WC must fall into the danger zone? Also for the small pipes, isn't there a 110mm danger zone?

Ah, I think I see what you are saying. Is the same true for the small bosses? If they are opposed, I don't think there is a sweep on them, or does the built in 2.5 deg angle alleviate the problem?

Hold on i'll find the pic.

Small bore pipe is 110mm zone.

Ah, excellent - so opposites are ok, it's only when you are connecting in the danger zones just below that you have a problem. That's a relief indeed. So you can use all the bosses at the same level on a section. I had it in my head that if they were directly opposing it was an issue.

Very many thanks - you have probably saved me quite a lot of work.

Simon

They don't make these for fun