Sealing Caravan Sink

[jadyn]

Hi All
I'm experiencing problems with a white plastic sink fitted into a small vanity unit in my caravan. The sink is made of white plastic and is about 30cm wide and is shaped similar to a conventional washroom sink. It sits about 25mm proud of the cut out in the vanity unit to accomodate the bowl. The back of the sink is semicircular in shape and the monobloc mixer tap sits in the the deepest part of the semicircle. The tap is not attached to the sink at all - it is fixed through a hole in the formica top of the vanity unit just at the back of the hole cut to accomodate the sink bowl. The gap between the back of the sink and the formica panelled wall behind is about 50mm at the deepest point.

My problem is that water is getting into the 50mm gap behind the sink and I'm afraid it will damage the formica panel behind the sink and the formica top of the vanity unit. It seems to be caused by people moving the swivel tap spout with wet hands allowing the water to run back down the tap body onto the formica. it just builds up there. I can't get any type of trim to fit onto the sink back as it semicircular in shape and angled, so sealing the wall panel/vanity top gap would be pointless. It's been suggested that I fill the entire gap with expanding foam. tool it and then paint it white, but I'm reluctant to do this as I don't have that much skill with the stuff. Besides the base of the tap has to revolve to allow the tap to turn. The underside of the tap spout sits in contact with the sink surface at the back of the sink so I can't even fit a thin sheet of acrylic across the gap - there would have to be a gap in the acrylic to allow for the tap body and this could be prone to leaking. Both the left and right hand sides of the sink are open and not against the wall. Any ideas please?

Thank you

[The Builder]

If I've got this right, it sounds like a fairly standard set-up. You have a vanity basin let into a deck, with a separate mixer fitted through a hole in the deck between the basin and the back wall.

This is a common problem in houses too. I really don't think there's anything that can be done except to keep mopping up the water occasionally.

Formica or laminate is made to take this in normal use. Even the cupboard deck can take becoming wet. Problems only arise when standing water is left there for any time.

Do make sure there is a good silicone seal around the basin and on the junction between the deck and the wall though.

[Ryzen]

You may find that the water is seeping through the o-rings fitted to the inside of the swivel spout. When the tap is turned off a small amount of water stays in the spout. If the o-rings are worn the water will seep out onto the deck.

[KARL]

I used to have a motorhome which had assorted challenges around the shower/toilet room, I think the more recent ones may be better designed and built but in this case I was surprised how short sighted the manufacturers were. I think I understand your description and from it it seems to me that the challenge is that you cannot do any building up around the base of the tap without reducing functionality, and the leak is right there at the base of the tap. It seems reasonable to fear long term damage to the horizontal and vertical panels, especially if they are of plastic coated chip/fibre board. The surface coating or formica type of material will in itself not come to any harm but what is underneath is vulnerable.

Without being there with you it is not easy to advise on what to do or how to do it. However, if you want to have a go at effecting a preventive process then the materials I would think best suited are plastic car body filler, hybrid sealant and Hammerite paint (white ?). The former is a two part compound which sets after a short time so you would need to be pretty clear on what you want to end up with as to a shape (don't mix too much of the stuff at once) - you can build up in stages and it sands pretty easily. Paint the finished shape(s) and use the sealant at the tap. You could try the sealant on its own if you think that might do the trick - mask off to set the limits neatly and have a piece of plastic tool/scraper ready cut to the shape you want the bead to end in (cut from a fairly rigid plastic container).

[jadyn]

Thank you all.