I live in a 6th floor of an old building with piping that clogs easily and frequently. We have to fix that, but it's expensive so we have to find temporary alternatives in the meantime.

Our washing machine has a drain hose that dumps the soapy water to a sink. The water coming out of the hose doesn't have suds, but as soon as it hits the sink, you can see the top layer of suds being formed. Our neighbor in the 1st floor sees these suds coming out of their dishwasher and rightfully complains.

On the other hand, to make sure it was the soap, we tested by filling the sink with plain water so it goes down the drain. The neighbor didn't see anything in her sink.

I know I can use less soap, but it will still make suds.

My question: what can I do to minimize the suds that go through the drain pipe? The ideal solution would be that the water in the sink does not have suds, so the water that goes down the drain does not have suds either.

Also, I just read that vinegar can reduce suds. But my concern is that the vinegar will reduce suds inside the washing machine and not the suds buildup in the sink when washing machine is rinsing.

  • This is an applicance usage question and not about home improvement.
    – isherwood
    Feb 4, 2020 at 17:58
  • dishwasher rinse aid kills bubbles like nothing else, as do all acids. The challenge is getting it applied at the right time. If you can reach the drain, squirt some in before running the washer. It will sit there or run a bit down until the wash water flushes it away.
    – dandavis
    Feb 4, 2020 at 21:41

3 Answers 3


If you use soaps marked HE (High efficiency) there will be less suds.

  • Liquid fabric softener could also help.
    – JPhi1618
    Feb 4, 2020 at 16:14

HE soap will improve the situation. But it seems the real problem you're having is the soapy water backing up into the first floor dishwasher. How is that even happening without waste water flooding the first floor kitchen?
You need to get the super involved in this. There are a number of ways to prevent backflow into a dishwasher which needs to be dealt with at the dishwasher. That's where the problem is. You shouldn't be expected to solve it from the 6th floor!


There are things like Laundry Ecoballs which don't cause suds at all.

You can check out the product at ecozone.com

No affiliation except a happy user.

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