How to Fit a Ceramic Undermount Sink – Kezzabeth

Last year, we installed a whole new kitchen for Grants parents. It was a very long job and took months to complete. It was so much work, that I literally had no time to blog anything about it. Having said that, I’ve already written about DIY fitting a kitchen before, so I didn’t really need to write much about it. However, there is a couple of different things I would like to write about. And how to fit a ceramic undermount sink, is one of them!

What is an undermount sink?

Essentially, as the name suggests – it’s mounted underneath the worktop, rather than on top. This gives a more streamlined look to your worktop as the sink appears almost sunken beneath.

The benefits are that it gives a much cleaner streamlined look to your worktop. It allows for more worktop space as well, which was the whole reason we chose it for Grants parents kitchen.

For certain lightweight sink materials, such as stainless steel – installing an undermount sink can be as simple as using clips to screw the sink to the underside of your worktop. However, for heavier materials, such as ceramic, this isn’t a viable option. Ceramic is extremely heavy and then if you imagine it full of water as well – this kind of weight could be enough to crack your worktop if the clips don’t fail beforehand.

So, ceramic undermount sinks need special attention when fitting them – to make sure they’re properly supported! I thought I’d do a very quick post, for how we overcame this issue when installing a ceramic undermount sink at Grants parents.

How to Install an Undermount Sink?

Step 1 – Cut The Base Unit (If Required) To Accommodate The Sink

First of all, you’ll need a base unit longer than your sink, so that it can easily slot inside. You’ll want to measure your sink and depending on its size, you need to decide how far forward you want it to sit against your worktop. Many sinks sit directly central, smaller sinks may be slightly further forward with a larger space at the back. This was the case with our sink.

Once we’d worked out where it would sit on the worktop, we could mark this up on the base unit. Depending on the design of your base unit, you may need to cut away a small bit of the frame.

Step 2 – Cut Two or Three Lengths of Wood to Create a Shelf Inside the Unit

In order to support the sink, we’re going to build a kind of ‘shelf’ for the sink to sit on. We decided to use CLS timber for this, as it’s cheap and strong. You’ll need your sink to sit 1mm or 2mm below the top of the unit – if it’s too high, your worktop won’t be able to sit flush, so lowering it a 1mm or 2mm will ensure it’s low enough. Measure the height of your sink, add 1-2mm and mark this up on the inside of your base unit.

Next, measure the inside of your base unit from the left to right side and then cut your timber to this measurement. It’s important it’s as mm perfect as possible, otherwise, you may distort the base unit frame and push the sides out, or pull them in.

Step 3 – Affix Your Wood In Place Using Screws

Screw through your base unit on either side to affix the wood in place. We used fairly long screws for ours, and when doing so, make sure your wood is level!

Carefully lower your sink onto the wood, to check it sits flush with the top of the base unit and that it’s also level. Assuming everything has gone to plan, your new shelf should hold the weight of your sink now!

You can add additional wood at this stage if you want to support your sink further. We actually added two pieces of wood to sit directly underneath the ‘lip’ of the sink as well. We felt ours was fully supported and confident it’s going to stand the test of time!

Step 4 – Fit Your Worktop On Top

When fitting your worktop, make sure to apply a silicone bead around the top of the sink before placing the worktop into position. This will stop water from escaping through any small gaps and keep the water directly in the sink area – where it belongs!

That’s it – pretty simple, I know. But I hope this was useful, or if you have any tips to add for next time, let me know below!

Tap featured is from IKEA, which you can find here.
Sink featured is from Tap Warehouse and can be found here.