I'm considering having my old system boiler replaced with a combi. This would give me the ability to remove the cylinder/airing-cupboard in the bathroom and provide extra room for a walk-in shower. The main soil pipe of the house passes through a boxed-in section in the bathroom and the drain from the existing sink and bath is tapped into this. The existing sink is next to the bath and the drain from the sink passes through the bath side panel and runs behind the side-panel (but above floor level) where it is joined by the bath drain before joining the main soil pipe. There is just a very short (6") length of the sink drain visible where it leaves the sink vanity unit and runs across the wall before reaching the bath panel. If I re-arrange the position of the bath, and sink and add a separate shower on the other side of the room, what is the normal way of dealing with the new drains? Would they run in a boxed-in section around the base of the walls?
Kev