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Plumbing

Can I reduce the diameter of the waste drainage pipe from my kitchen sink

Anonymous user 09/03/2024 - 2.48 PM

Hi, I've just moved into a new build and bought an integrated dishwasher and attempted to fit it in the designated space in the kitchen, but I can't slide it back as far as if like as the waste drainage pipe from the sink/washing machine runs along the back of the recess. Just wondering if it's possible to fit a slightly narrower pipe back there so I can slide the dishwasher back an extra cm or if that will mess up the drainage?

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5 Answers

K Building

Rating: 4.8 out of 5
Aylesbury
It depends on the diameter of the drainage pipe. As a principle, a drainage never should be reduced, on the flow sense. The diameter should increase, not decrease. If the pipes from sink and washing machines are 32 mm, than you could make that pipe that bother you of 40 mm, for example. But I think the best solution is to move/divert that pipe trough the wall, partial or total. You could make a trench and set the pipe partially into the wall, 10-20 mm.
Answered20 March 2017
3

Oliver Butterworth

No reviews yet

Blackheath, London
Hi, the waste pipework from your kitchen sink should be a minimum of 40mm diameter. It would be better if you could re route the pipework from under the sink directly to the outside, if the sink is on an external wall. If not chase the pipework into the wall internally to give you the extra space to get the dishwasher in.
Answered21 March 2017
1

Anonymous user

Try and take waste pipes outside but if you have an internal soil stack chase pipes into wall.
Answered21 March 2017
0

Anonymous user

Never reduce the pipework which is minimum of 42mm you will end up blocking the sink up and creating a problem. I would take the pipework from under the sink and run it outside that would be the best option. If not you will have to chase out to fit the dishwasher in place.
Answered21 March 2017
0

BM Plumbing and Tiling Services

Rating: 1 out of 5
Brighouse
If there's enough length on your hoses on your machines .. you could fit a new sink trap that you can attach your hoses to.. so no need for waste pipes
Answered21 March 2017
0