Extend soil pipe for shower waste advice

[mentalmike]

Thanks for all the suggestions everyone!

So I'm thinking about going with...

In my photo it didn't show to the right that there is a boss strap for the bath waste. Seeing as the general consensus is to cut the old ring seal connector off I thought I could do it further to the right to get rid of the strap with a proper boss. Also none of the current run seems to have any clips and is just floating around under the floor so can add a couple of clips to the joist.

So my plan is to cut off old ring connector, solvent weld short boss for use for bath waste, section of new pipe solvent welded in, solvent weld double coupling to 112.5 branch. Can't find any solvent weld 112.5 branches at both ends (solvent weld seem to only be 92.5 and 135) so then a push fit reducer which I can solvent weld shower waste into.

How does that plan look? I assume with the old pipe I shouldn't have too many issues solvent welding it to a new boss as long as I cut it square, clean it up and debur properly? I can't find any markings for a brand to try and use the same.

 

[Madrab]

I'd keep it all solvent weld, even the branch.

So you'd go straight from the boss coupler > a small piece of pipe > fit the branch to that > then the waste adapter. You'll want a vertical section of pipe into the branch for the pan connector too.

 

[Madrab]

Meant to say, a 92.5deg branch should be fine as long as there is enough distance from the end of the 40mm waste pipe before the downflow from the toilet branch. Given the 110mm adapter has a stop in it so the terminal end of the waste pipe will always be clear from the downflow from the loo, as such there shouldn't be any vacuum or crossflow created.