Kitchen Sink - sealing

[marshr02]

What's the best way to seal a S/S inset kitchen sink?. I know this is possibly a basic Q, but I'm getting lots of different answers. I'm keen not to get any leaks and blow the worktop!

The sink came with some form of putty strip, that I've managed to damage by fitting sink and then pulling out again because I needed to fit the brackets to the sink before fitting the sink.

I was going to run a bead of plumbers mate on the lip, followed by a bead of fernox ls again on the lip towards the edge. The plumbers mate to allow mechanical bedding in, while the fernox is going off - with the fernox ultimately being the sealant.

Some people say use 100% silicone sealant, some say 100% plumbers mait - but the plumbers mate instructiuons suggests a sealant is also used with sinks

Thanks for any help...

 

[migoplumber]

i think youll find its down to personal choice,
ive always used silicone and plenty of it, then screw the sink clamps down, watch the silicone all bubble out round the edges, leave for 24 hrs then cut off excess with a sharp blade. never had a problem. just pity the bloke that comes to change it in 10 years time.

dont forget to silicone seal the exposed chipboard in the worktop, that way if you do have a leak, the board is still protected.

shaun

 

[marshr02]

Thanks for quick reply. I'm guessing the laminate worktop has a life equivalent to a S/S sink, bar any breakages - so the removal is less of an issue..

 

[Bernie2]

Err!


Plumbers Mait whilst good on cold surface joints, if it gets hot it goes like liquid!

Don't forget anti fungus or anti mould ability in the sealant, favour like Migo, good silicon sealant. Apparently the cheaper silicon sealant can be bulked out with chalk by the makers to fill the tube. So stick to a good make. If you want a really good seal I like Dow Corning, its dear but good.

Pvc windows by the way, are said by some in the PVC window trade, best sealed with Low Modulus Neutral cure sealants. That is a bit of useful info I picked up on a window fixers website.

Apparently the Low modulus means its highly flexible and High modulus means it goes hard.

 

[marshr02]

In the end, I used Fernox LS. I guess an expensive silicone sealant - 3 tubes @ £3 each from screwfix. Looking good so far...

 

[MarkB]

I know it's a bit late but as Migo say's - sealing the cut edge is really important as this is where you'll get the most problems with water penetration. smear on a good amount and work it onto the edge with a gloved finger.

When cleaning off any un-cured silicone, spray it first with a 50/50 solution of washing up liquid and water. It will make cleaning up so much easier.

Mark

 

[Bernie2]

Applying sealant

I bought one of those Fugenboy packs from Screwfix, its great. One of the things I am useless at is silicon sealing. I tried all kinds, wet finger, washing up liquid, setting in tools all kinds, but could never get it the way I wanted it. The Fugenboy seems to do it though.

But just because I am useless at getting it straight and need a trowel tool to do it, does not mean others can't do it with their finger and a bit of washing up liquid.

Incidentally, not thinking, I used washing up liquid on my finger for a silicon job once, then for some reason I've forgotten sucked my finger afterwards. I was spitting it out for hours!

 

[marshr02]

MarkB - not too late. I sealed the cut edges by first using a paint primer to reduce suction and then silicone as belt & braces.

The Fernox LS seems to have done a good job but still have bits of it on the worktop that I can't get off yet. Might try silicone eater chemicals....

 

[billybongo]

I thought fernox Ls was a leak sealer , i have never heard it used to bed a sink in ? usually paint inside the cut out with varnish , then the seal supplied or silicone sealant .

 

[MarkB]

The problem with LSX, as you may have found, is that it is much thicker than a regular silicone sealant. It's intended more for use as a leak sealer and jointing compound.

Be careful with the silicone eater, you don't want to compromise the seal you've already made.

 

[marshr02]

Thanks for the replies. Since using Fernox LS I've never had a single leak anywhere - although you're right about it being thicker. When I was cleaning up wiped the surplus stuff off my hand onto the other halfs favourite china plate. Couldn't get it off....

I guess next time I'll try using normal silicone, maybe it's easier to use?

When the other half uses the sink, there's usually a lake of water nearby. I get the feeling the sink could be submerged in water and this seal would hold firm...

Would like to be there when someone tries to remove the sink.....

 

[bcp]

I always use Silicone. When it's curing, I have the sink half full of water if at all possible, just like I do with a bath.