need plumber's advice (or those who had the same issue) - splashing from the sink!

[likeatonneofbricks]

It looks like when the flat upstairs uses their washing machine (could be dishwasher but not likely), I get a fountain splashing out from my (low set) sink in the kitchen, which leaves white residue. It happened twice when i was out so I couldn't see it but the water and the white residue is around sink area although it goes quite away from it and covers kettle even (horrified how high must it splash as it's butler's sink!). Fed up mopping it up but also it now left indeilible rust stain on wood top as I was away and didn't wipe it quickly. The water when wiped seems a little dirty but tere is a smell which a bit sour/chemical. I really hope it's nothing too serious and can be fixed? don't want to go to them before i know what I'm talking about (hardly met them yet). Is the stuff dangerous to ingest in small amounts as it did splash at kettle (when boiled afterwards quite a strong sour smell came when heated, of remaining few drops - I did wipe it again and it stopped smelling but a tiny amount could have got inside).

you mean coming out of the plughole?

then there is probably a blockage in the soil pipe to which your drain, and theirs connects; otherwise the pipe runs have been done extremely badly.

It is not likely to be anything your neighbours are doing wrong (unless it is leaking through the ceiling).

Such bad plumbing is more likely to happen in an old house that has been converted into flats than in a purpose-built block.

If you are not fond of plumbing, start asking around for local recommendations.

Until fixed, get into the habit of leaving the plug in, perhaps with something heavy on top.

Yeah, must be a blockage somewhere. This used to happen in my parents' house during very heavy rain. It eventually turned out tree roots had cracked and blocked a wastewater pipe outside, right after the point where it was joined by the pipes draining water from th flat roof. At times where there was a lot of water coming off the roof, the blocked pipe couldn't cope and the water would look for a way out, namely back into the house and up the sink plug. You'll need to get a plumber out I guess.

PJ this IS an old Victorian house, converted.
I looked closely this morning - there are marks on the ceilling! nothingis dripping and freshly wet, but yellow marks along the ceilin in couple of places and also lines across (as if along floor boards above). This looks like a leak,old or new, but it seemed to coincide (the splashes) with the rain yesterday. Could it somehow come from rainpipes this far into the kitchen, Naoko? this is not ground floor, but a high first floor, unlike your parents i assume. They used the machine today on a very short cycle and nothing splashed, but possiby long cycles last time (few in a row) cause it?

*like last time

No I imagine it's probably not rainpipes for you, but it could still be a blockage that means when your neighbours use their washing machine, the pipes wfor the wastewater can't cope and the water washes back into the house, that's what I was getting at - apologies if that wasn't clear!

This happens when we use our washing machine, white foam comes up through the plug hole of the kitchen sink next to it. It must be water from the washing machine as it is foam and smells of detergent. I think we also have dodgy plumbing so that the sink and washing machine must join somewhere in the plumbing although my dh is adamant that is is not the case!

get then to check fully around the back of their machine and the pipes.

could be a slow leak somewhere where they haven't noticed

Naoko so you mean it's the main waste pipe of te whole building that's blocked (and then the flat below should be getting same problem) OR just theit waste pipe of the w.machine? I think you meant the main one. There aer water marks on hte ceiling though even though not strong (so more likely their machine).
south - yes I'm emailing their landlady as the it's useless talking to tenants!
I wonder whether she'd be willing to pay the plumber or wlil demand contribution?
frankie - it's not from my own machine (it's nowhere near).

Most likely, the kitchen wastes from all the flats all go into a single stack, which will be a 100mm vertical pipe. You will probably be able to see this stack, either on the wall outside, or running in a corner of the kitchen. It may be boxed in or hidden behind kitchen units. It might be iron or plastic.

If water is coming out of your sink, then the blockage will be at or below the point where your sink waste joins this stack.

If it does not come out of the sink in the flat below you, and if their sink is connected to the same stack, then it will be at or above the point where their sink waste joins it.

If the same stack also has WC outlets connected to it, then sewage will be among the material.

thanks PJ. the WC is not close so I think it's separate (there is long pipe running outside on the side of the building, a wide one). the waste is more like mild acid of maybe dishwasher stuff - it soesn't smell bad just 'chemical'. But as there are lines on the ceiling I think something must be leaking under the floorboards of the flat above (from some pipes) - I think the dripping MAY hav been not from my sink plughole but from the lights (recessed) in the ceiling, but I didn't see it. no obvious water around the lights but the splash was in places under them which also by the sink.

the wide pipe on the side of building is not near the kitchen, which is in the front corner, so quite removed from it.

then it might be a leak in their kitchen dripping through the holes in the ceiling where the lighting cables come through.