I am plumbing first fix in self build which has timber 50mm by 37mm battens which form the service void where cables and pipes (15mm) will run.  Question is how do the pipes which are plastic exit through the plasterboard to service sinks, toilets etc.  Is it just a case of knocking/drilling a hole in the plaster board and feeding them through or is there normally some sort of interface box/fitting used.  Appreciate any advice from those who have done this type of build before.  regards

 

Yep - 90 degree Hep2O elbow and a Talon pipe cover over the holes. 

Kitchen Sink- would bring them through a hole in the plasterboard low enough to allow for the length going to the tap so the only joint is at the isolating valve under the sink.

 

 

Toilets- use a cold forming bend on the pipe to get a bend on the pipe and then a right angle fitting to take you into the cistern