The waste pipe under the sink is about 5cm below the bowl of the sink. I need to reconfigure what the plumber has installed as there are smells coming up. I know it's a high waste pipe and best to lower it but if possible I'd like to reconfigure what exists. Any suggestions welcome.

The white corrugated pipe far left is main bowl overflow

The metal hoses are hot and cold water into the tap.

The grey pipe with red tape is washing machine.

Black is waste pipe.

Left side is the main bowl, right side is drain basket (connector sealed).

current configuration

  • Q: when you sayd "washing machine" are you talking clothes, or dishes?
    – Huesmann
    Commented Jun 9, 2023 at 18:44
  • "The standpipe for a clothes washer should be at least 18 inches and not greater than 42 inches above the trap weir. The standpipe should be at least 2 inches in diameter." nachi.org/school/internachi-university/…
    – Mazura
    Commented Jun 10, 2023 at 2:48
  • Are you prepared to cut into the back-wall lining and see where the waste pipe goes? Or get your head or a mirror or one of those little cameras in? If you could lower the hole through the wall then you'll get more height to work with, which will then allow you do do it right.
    – Criggie
    Commented Jun 10, 2023 at 3:37

3 Answers 3


Here is what you should do temporarily until you properly open the wall and lower the drain pipe.

  1. The trap is in the wrong place. There is an open air path from the drain pipe to the drain basket and laundry. Hence the smell. The larger sink should use a 90 degree bend to join the tail of the drain basket BEFORE the trap. This picture shows the overall layout, it does not show the correct fittings to use:

enter image description here

Same design, presented on the original photo.

enter image description here

  1. The laundry should not be joined with electrical tape. Usually appliance hoses are connected to such fittings with hose clamps. If that grey pipe is rubber, that is what you should do.

The above isn't a good solution but it's a lot better than what you have. The main sink may not drain well. The laundry may wash up into the main sink.


There may not be enough vertical space to configure this. I can't tell from the photo. If not, you'll need a pump. Move the trap as described above but join the main sink to it via a Utility Sink Pump that would sit in the cabinet. You'll need electricity there. The cost of doing this may be similar to fixing drain connection properly.


Get a shallower sink and eliminate the drain basket. Then you'll have a vanilla installation.

  • No luck. Waste too high... Seems likely a costly job that the original kitchen fitter could have prevetend! Commented Jun 9, 2023 at 17:19

Wow, what a mess. I can see why you've got smells coming out of there. A lot of the waste water never sees the drain. At this point, you'd be smart to remove the wall and expose the drain pipe and figure out a way to lower the connection so your traps are inline with it.

  • 1
    I know. The guy who fitted the kitchen has left the country. Problem is the waste pipe connected externally to the main waste stack is already low and connected to the toilet. It's would be a last resort and do doubt cost a lost of money to get a professional. Hoping that I can reconfigure as the the waste is lower that the bottom of the large bowl, not by much but hopefully enough to allow correct water flow. Commented Jun 9, 2023 at 13:00

l bent and moved the ptrap as shown

l bend and moved ptrap

  • 2
    That's not going to fix the issue with smells. You need to have the trap between the wall and your items. The smell comes from the wall, and the trap blocks the smell when installed correctly. It looks to me like your only option to really fix this would be to open the wall and move the wall connection lower. I might add an additional y connection that could be used for your washing machine or second sink to simplify things. The flex coupler at your connection to the wall is very likely going to lead to leaks over time as well, so best to get it all connected and fixed correctly. Commented Jun 10, 2023 at 0:03
  • Functionally, this is identical to what you started with. Your goal is to have the waste pipe through the wall immediately "after" the p-trap. All the inputs have to be "before" the p-trap.
    – Criggie
    Commented Jun 10, 2023 at 3:45

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