Soil stack change - is this OK?

[TeaAndBiscuits]

I'm redoing my upstairs bathroom and have changed the positions of the soil pipe and shower/bath waste exits

Is there any reason (e.g. regs) that I can't or shouldn't do it like this with a Y then boss the 40mm bath waste into the new vertical bit of branch?

I'm anticipating a question along the lines of - 'why dont you just bring the elbow out sideways and straight into the stack and boss the bath waste on below it?'

The reason I dont want to do this is that the original stack is set away from the wall by these wierd old metal pipe clips set to match the old clay part set in the ground, all of which needs re-doing (including the part in the gound) at some point. This way I can do my new bit with the correct wall clips/spacing, then not have to mess around with it later when I redo the vertical main stack. If that makes sense.

 

[blup]

Don't see why not, the venting won't be affected.

Blup

 

[Justin Passing]

May need a deep or resealing or vented trap on the bath -if it tries to "pull"

 

[Hugh Jaleak]

Personally would set the stack in the correct position now, use an adjustable bend to line the bottom up to meet the drain, then ditch that when you redo the rest bend etc at a later date.

 

[TeaAndBiscuits]

Bosh! Got this done at the weekend. Ideally I would have liked to take Hugh Jaleak's suggestion and sorted out the vertical stack as well but for various reasons, it's just not possible for me to do it at this time.

So this will have to do. A million times better than what was there before.