Kitchen sink waste leak in floor


6 May 2023
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United Kingdom

Where the waste pipe from my kitchen sink goes into the floor, there is a rubber seal and the floor is wet/damp (I've marked the seal and wet floor with red in the photo). The pipe is dry, so it seems to me that there is a leak between the seal and the floor. I am thinking of disconnecting the pipe from the sink trap, pulling out the pipe and replacing the seal (and also cleaning the area, there seems to be some debris between the seal and the floor). What is this seal called, if I am to go to a store to buy a new one? Also, is the orange thing (marked with the blue arrow) the waste pipe in the floor, and do you think it might be the cause of the problem and not the seal?


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The orange pipe is standard 110mm underground drainage, the rubber 'seal' is a 110mm to 40/32mm rubber reducer but it doesn't look like it's all the way seated.


It shouldn't really leak from that spot though as it should all be downhill from there so there may be a restriction in there and it's backing up a bit. That 40mm reducer will just pull up out of the soil pipe even with the 40mm still in there but always better to remove it first and then you can see what's going on under there.
Thanks, that's very helpful, I will give it a go.
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Also depending on what type of soil pipe fitting is in the floor, you may be able to use one of these which may be a bit better.


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