Nail the hit head on have you.
It's the ball ache of going all the way to the top of the slate roof and cutting the CI into sections, then passing it back down piece by piece. If I can leave the CI in place and work with it it would be a much easier / cheaper solution.
I will shortly be moving my bathroom into the next room along, leaving the current one intact until most of the work is done and waste connections need to be made ( less earache).
It is a 2 pipe system with a cast iron soil stack and waste water and rain water running into a hopper. The two...