We have quartz worktops with a white plastic double bowl underslung sink, this was adhered to the underside of the worktop at the time of the original fitting, it's starting to come loose at end where the smaller bowl is and a gap is appearing allowing water through, it looks like I may have to disconnect the wastes, remove the sink and refit it, what will be the best adhesive to use?

Hi @80's Owl

 

Not sure of your set-up but here's a helpful guide. 

 

M

 

https://www.thespruce.com/after-reinstalling-sink-reapply-caulking-1822208#:~:text=Undermount sinks are secured beneath,need to be re-tightened.

In case you don't have any luck with adhesive we used G Clips for attaching our underhung sinks to our granite worktops.

 

https://www.gclip.co.uk/Undermount_sink_installation.html

 

 

33 minutes ago, Gone West said:

In case you don't have any luck with adhesive we used G Clips for attaching our underhung sinks to our granite worktops.

 

https://www.gclip.co.uk/Undermount_sink_installation.html

 

 

 

I don't they'd be suitable as we don't have that thick lip on the sink edge.

3 hours ago, 80's Owl said:

 

I don't they'd be suitable as we don't have that thick lip on the sink edge.

We fitted a Schock sink which had a flat flange about 8mm thick IIRC.

1 hour ago, Gone West said:

We fitted a Schock sink which had a flat flange about 8mm thick IIRC.

 

The lip on ours is only about 4mm, someones recommended a CT1 adhesive.

1 hour ago, 80's Owl said:

 

The lip on ours is only about 4mm, someones recommended a CT1 adhesive.

I looked at using adhesive for ours, but when I thought of the weight of a double sink full of water I decided to fix it mechanically.

12 minutes ago, Gone West said:

but when I thought of the weight of a double sink full of water I decided to fix it mechanically.

Yes CT1 is very good but being OCD I would want some sort of mechanical support with that potential weight. Even a timber support within the cupboard would be more than enough/considered.

1 minute ago, joe90 said:

Yes CT1 is very good but being OCD I would want some sort of mechanical support with that potential weight. Even a timber support within the cupboard would be more than enough/considered.

 

I do have a timber cradle under it tbf but it's under the main bowl, its coming away from the worktop where the half bowl is as it's shallower, once I've redone it ill put someting in to support that as well.

Well the sink should not bend so timber support on the main bowl should suffice but not difficult to add a bit to support the smaller bowl as well 👍