I have just hit a snag in the installation of my new kitchen. The problem im having is my new sink is undermount and has lowered the p trap to a point below the outlet in the wall, I dont think that lifting the sink is a practical option as I will have to lift the countertop approx 100mm, my other option would be to drill a hole in the outter wall and reconnect the drain pipe at a lower level, does anyone know if there is any issues with this and is this a DIY project or should i get a plumber to advise? Cheers James
This is something most DIYers would/could take on. It does involve quite a lot of work if you don't have a masonry hole cutter, so you might want to get in a few quotes from local plumbers. It boils down to how much you consider your time to be worth.
Just core drill a new 2" hole through the wall. If when through the wall the existing pipe is connected to a stack you might need to fit a new boss if the connection is not low enough. If it goes into a hopper you might need to lower it, if a gully you will be fine.