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  • FIRST POST
    • d0nkeyk0ng
    • By d0nkeyk0ng 17th Oct 16, 10:27 AM
    • 253Posts
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    d0nkeyk0ng
    Bathroom sink leak
    • #1
    • 17th Oct 16, 10:27 AM
    Bathroom sink leak 17th Oct 16 at 10:27 AM
    The wife's noticed that there's water on the floor under the sink in the bathroom. At first we put it down to me being messy. But it persisted over the last two weeks and I've had today off so I investigated a bit further.

    I cleaned the area dry, stuck newspaper under the sink and then slowly ran the taps so the bowl was full but didn't run up to the overflow hole. There was water slowly leaking (drop by drop) on to the newspaper. I can't feel any wetness from around the trap or waste pipe but the bottom of the sink is wet.






    I've attached pictures. The red circled area is the bit of the sink that's wet. There's no cracks that I can see in the sink. Any ideas where the water's travelling through?
Page 1
    • Stevie Palimo
    • By Stevie Palimo 17th Oct 16, 10:32 AM
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    Stevie Palimo
    • #2
    • 17th Oct 16, 10:32 AM
    • #2
    • 17th Oct 16, 10:32 AM
    If you are not messy enough for it top be coming over the top of the sink and the pipes seem dry and the sink seems crack free then it must be on the waste outlet/pipe area that is leaking slightly.

    You could try and check the plug area by removing the part you see and seeing if the rest is tight enough and if so then it must be underneath.
    " I refuse to censor myself because it may offend someone. If you don't like me that's ok, I don't need your approval. "
    • Ruski
    • By Ruski 17th Oct 16, 1:21 PM
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    Ruski
    • #3
    • 17th Oct 16, 1:21 PM
    • #3
    • 17th Oct 16, 1:21 PM
    Fill up the sink and watch it drip - that will tell you where it's coming from, if nothing happens after 15 minutes, fill to the overflow and watch it again. (may be only a crack in the overflow part of the porcelain)

    Report back!

    p.s. flexi waste connection? Could someone not be bothered??!!

    Russ
    Perfection takes time: don't expect miracles in a day
    • JohnB47
    • By JohnB47 17th Oct 16, 1:49 PM
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    JohnB47
    • #4
    • 17th Oct 16, 1:49 PM
    • #4
    • 17th Oct 16, 1:49 PM
    Interesting. It looks like the overflow is internal to the bowl - I can't see any external pipework for that.

    An observation - the waste fitting, when viewed from below, seems not to be fitted centrally in the hole. Could it be that water is creeping around that black rubber sealing washer because it's not fully sealing the area? If so, depending on the shape of the underside, it could explain why that drip is there. Water could be creeping past the washer, then along the underside of the bowl to the lowest point, then dripping down. The position of the damp patch on the paper would support that idea.


    I second the idea to check where the water is coming from, first by filling with cold water, then with hot - the heat may open any cracks that are there. Use a torch.
    • d0nkeyk0ng
    • By d0nkeyk0ng 17th Oct 16, 1:55 PM
    • 253 Posts
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    d0nkeyk0ng
    • #5
    • 17th Oct 16, 1:55 PM
    • #5
    • 17th Oct 16, 1:55 PM
    Fill up the sink and watch it drip - that will tell you where it's coming from, if nothing happens after 15 minutes, fill to the overflow and watch it again. (may be only a crack in the overflow part of the porcelain)
    Originally posted by Ruski
    Yep planning to do this. I've just poured water straight down the drain but managed to spill a bit into the sink so waiting for it to dry a little and retry.

    p.s. flexi waste connection? Could someone not be bothered??!!
    Originally posted by Ruski
    I know. Looks odd. This is how things were when we moved in last year. What should the waste look like?

    Interesting. It looks like the overflow is internal to the bowl - I can't see any external pipework for that.
    Originally posted by JohnB47
    It is. There's a small "bump" running from the back of the sink to the waste. The rest of the sink underneath is a smooth round bowl.

    An observation - the waste fitting, when viewed from below, seems not to be fitted centrally in the hole.
    Originally posted by JohnB47
    It looks fairly central to me but I'm not really experienced in plumbing things yet.


    I second the idea to check where the water is coming from, first by filling with cold water, then with hot - the heat may open any cracks that are there. Use a torch.
    Originally posted by JohnB47
    Will do.
    • Carrot007
    • By Carrot007 17th Oct 16, 2:01 PM
    • 293 Posts
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    Carrot007
    • #6
    • 17th Oct 16, 2:01 PM
    • #6
    • 17th Oct 16, 2:01 PM
    Adding some food colouring to the full sink may help you see where the drip is coming from.
    • Grenage
    • By Grenage 17th Oct 16, 2:03 PM
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    Grenage
    • #7
    • 17th Oct 16, 2:03 PM
    • #7
    • 17th Oct 16, 2:03 PM
    I normally cable tie tissue paper around joins, when I'm having problems locating leaks. Helps you narrow down the source.

    In this case, if there's no crack in the sink, it must be coming over from the side or back.
    • d0nkeyk0ng
    • By d0nkeyk0ng 17th Oct 16, 2:36 PM
    • 253 Posts
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    d0nkeyk0ng
    • #8
    • 17th Oct 16, 2:36 PM
    • #8
    • 17th Oct 16, 2:36 PM
    I added some red food colouring but it didn't help.

    I did a few tests but realistically I think I need the sink to dry out fully before trying again.

    1. Used a plastic water bottle with the bottom cut off as a funnel. Took the top of the click-clack plug off and poured water directly down the drain. No leak.

    2. Filled with cold water to overflow - leak (one drop every 10-13 secs)
    3. Filled with cold water so level was below overflow - leak (as above)
    4. Filled with hot water to overflow - leaking a bit quicker (one drop every 8-10 secs)
    5. Filled with hot water so under overflow level - leaking a bit quicker (as above)
    6. Opening the plug after steps 3 and 5 - leaked a bit more quickly (every 5 secs)

    The trap/waste area is bone dry. I've been checking by running toilet paper around each section. The moisture is always from the red circled area.

    To me, this means the trap/pipes are okay but either there's a leak around the plug hole, or there's a crack under the plughole that can't be seen from the outside.

    Any suggestions how to proceed? I plan to leave the sink alone for a few hours to make sure there's no water dripping and then do the same tests as above.
    • JohnB47
    • By JohnB47 17th Oct 16, 3:07 PM
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    JohnB47
    • #9
    • 17th Oct 16, 3:07 PM
    • #9
    • 17th Oct 16, 3:07 PM
    If the whole area is dried off before you set the drip off again, can't you feel around with your finger to see if the water is tracking from somewhere else to that point where the drip is?


    I'm still betting on a weep of water coming from above that black sealing washer, along the underside of the bowl, to the drip point. Simply wiping your finger along the underside of the bowl should help track the flow path of the water.


    If the area around the drip point is dry, then there must be a crack in the bowl, which I think is unlikely.
    • Ruski
    • By Ruski 17th Oct 16, 5:24 PM
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    Ruski
    It's really difficult to get the perspective for the bottom of the bowl - it 'looks' like the waste outlet of the bowl is low, then the ceramic goes 'up hill' before coming back down to the outer level (all as viewed from underneath).

    If this IS the case then it can't be the waste connection as water can't run uphill - unless there's a part of the bowl we can't see which is at the same level as the waste outlet ?
    Perfection takes time: don't expect miracles in a day
    • Le_Kirk
    • By Le_Kirk 17th Oct 16, 5:49 PM
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    Le_Kirk
    I'm with this ^^^. I cannot see how water can run uphill unless it is the perspective of the photo. OP, why didn't food colouring help? If water is coming from the waste outlet and tracking across to the side of the wash basin, you should be able to see it. If it is just coming from a crack, there would be now water (coloured or plain) tracking across the basin.
    Last edited by Le_Kirk; 18-10-2016 at 9:20 AM.
    • JohnB47
    • By JohnB47 17th Oct 16, 7:00 PM
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    JohnB47
    I'm sure the OP will come back soon but I'm looking at the way the bottom, around the fitting, seems to be moulded deeper round the back - behind the chrome bits.

    I think the sink base comes down lower here, to accommodate the internal waste channel and I'm wondering if this brings a part of the ceramic base lower than, or on the same level as, the black sealing ring and would allow water to track across.

    Very difficult without more pictures.
    • Marktheshark
    • By Marktheshark 17th Oct 16, 7:18 PM
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    Marktheshark
    The top seal on the plug hole is leaking, the water is getting in the hollow porous part of the sink and draining through.
    Take the plug out and replace the top seal
    Brexit will become whatever they invent it to be.
    • d0nkeyk0ng
    • By d0nkeyk0ng 17th Oct 16, 7:35 PM
    • 253 Posts
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    d0nkeyk0ng
    OP here. The area around the waste feels dry. The wet area is just the area that I've highlighted.



    I've drawn an outline of the sink as it feels to me:



    The leak does seem to extend from one side of the waste channel to near the front. The area is wet. The water is definitely not coming from around the waste under the sink. No idea if it might be coming from around the waste on the other side of the sink.

    If you need more photos, please let me know what you need them of or what angle and I'll try to get them. There's shelves under the sink which make it difficult to get a direct view from underneath but I'll try in the daylight tomorrow.
    • d0nkeyk0ng
    • By d0nkeyk0ng 17th Oct 16, 7:38 PM
    • 253 Posts
    • 88 Thanks
    d0nkeyk0ng
    The top seal on the plug hole is leaking, the water is getting in the hollow porous part of the sink and draining through.
    Take the plug out and replace the top seal
    Originally posted by Marktheshark
    This is what I think is going on. There are no cracks that I can see but am going to try to get photos from behind the waste (under the taps).

    I know how to take the click-clack plug bit off, and I gather the spindle it sits on just needs twisting off. But how do I remove the top bit of the plug and reseal it?

    Also should I reseal using silicone, plumber's mait/putty or a rubber washer type thing?
    • Marktheshark
    • By Marktheshark 17th Oct 16, 7:41 PM
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    Marktheshark
    What has confused you is the construction of the bowl, it is hollow inside, if the top seal on the waste plug leaks the hollow part in the center will fill up and unless glazed, it drains straight through.
    Brexit will become whatever they invent it to be.
    • JohnB47
    • By JohnB47 17th Oct 16, 8:25 PM
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    JohnB47
    This is very odd.

    OK, it's not leaking past the black sealing washer but my understanding of these fired clay sinks is that, even if not glazed, they would be non porous. OK, perhaps not totally so but like a clay plant pot, not likely to let water through to that extent.

    Perhaps the firing was faulty or there is a hairline crack?
    • Marktheshark
    • By Marktheshark 17th Oct 16, 8:27 PM
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    Marktheshark
    It has a top washer and a bottom washer, the top one is leaking, it is hollow, yes it is porous and the bottom is made open so it fits on the mold and sealed afterwards.
    Brexit will become whatever they invent it to be.
    • JohnB47
    • By JohnB47 17th Oct 16, 9:06 PM
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    JohnB47
    You obviously know how this sink is made. So am I right in thinking that the sink is made first, with a huge hole in that bottom bit and a smaller sink hole, then glazed? Then a separate bit, moulded on its own, is put in place and sealed on somehow (with the glazing first having been ground off both parts where they join)?

    If so, perhaps the joint between the two is faulty. (Sorry, I still can't accept that fired clay is porous enough to let drips of water through).
    • d0nkeyk0ng
    • By d0nkeyk0ng 18th Oct 16, 3:08 PM
    • 253 Posts
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    d0nkeyk0ng
    Right guys, big update time.

    I removed the waste trap. The basin wasn't secured down in any manner, so I just lifted it up.

    This is the underside view:



    You can see the overflow at the back.

    And here's what I saw on closer inspection:



    This is the area that's been wet all this time. The leak has been coming out from here for sure. I've closely examined the rest of the sink and can't find any other cracks.

    I removed the large nut at the bottom:



    There was some silicone there.

    This is what was left when I removed the waste flange:



    And after I cleaned it up:



    I can't see any cracks anywhere in the basin. The overflow empties into the main drain. Is it possible that water is backtracking and enters the interior of the sink at some point and then leaks through the crack?

    I plan to refit the waste flange and put everything back together.

    1. How do remove the remnants of silicone? I've scraped what I can off with a stanley knife. Or should I just leave it?
    2. Do I use new rubber washers?
    3. There's a rubber washer that fits between the waste flange and the basin on the top side. I've seen a youtube video where the chap just uses silicone instead of a washer here.
    4. Before I replace the bottom washer, should I use silicone here too?
    5. Should I bung up the overflow spout with silicone?
    6. What can I do with the crack? Leave it or silicone it or do something else?

    Apologies for all the questions but I really need some help and advice on what to do next. Wasn't planning to do any bathroom renovations until 2018 and we were going to get the whole bathroom refurbished.
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