In message
, ian
writes
My question is how do I connect 100mm PVC to the existing 4 inch cast
iron? I asked Marleys and they offered a push fitting for a 4 inch
cast iron spigget but I do not want to cut the 4 inch pipe, there is
no easy way of doing it in the position its in.

Ideally I will connect the 100mm PVC into the cast iron socket in the
branch on the main soil stack. How can I connect PVC into a cast iron
socket easily?

When I did the same sort of thing in my old house, i found that the
plastic soil pipe was a pretty good fit into the CI socket (just clean
out the putty stuff they used to seal the joint if it has any).

I just used some sort of mastic/sealant to then seal the joint. I foget
what I used,it might have been that 'Gutter and Drainpipe sealant'
--
Chris French