Kitchen sink outlet leaking

[setanta1]

Looking for advice on a problem in my kitchen. The outlet from the sink (which is also plumbed to the dishwasher and washing-machine) goes out through the wall just under the sink. On the outside wall there is a large damp patch around the outlet pipe and the floor in the kitchen, under the kitchen units, is also wet. It looks to me as if the leak in the pipe is in that part of the pipe that is within the wall. Any thoughts on how to proceed? The only things I can think of are to either drill a new hole in the wall and move the pipe slightly or drill out the existing pipe and replace it. Both seem like big jobs to me.

 

[Carpenter]

The plastic pipe, probably 40mm waste (11/2") and it's elbows etc are at fault. Possibly failed solvent joints. It should be easy enough to cut off the pipe and tap it through the wall, using a cold chisel to help break it up. when replacing the pipe be sure that the new section of pipe and any solvent weld fittings you use are clean and dry. Abrade the meeting surfaces with sandpaper and apply plenty of solvent cement. Don't use the completed pipework for a number of hours and avoid discharging hot water down the pipework for at least 12 hours. This job is not technically difficult- tight access is the real problem.

 

[setanta1]

Thanks Carpenter. I'll set about this and report back on how I get on. Don't hold your breath, my wife says that D-day took less planning than some of my DIY jobs!

 

[Carpenter]

Just make sure you have a bucket and old towel at hand to catch the mess when you disconnect the "P" or "S" trap. Take your time and do a dry fit on all the components (mark their relative connections with a pencil) before you even open the bottle of solvent weld cement!