How to Fit a Bathroom Vanity Unit

A vanity sink is one of the most important and on-trend pieces of bathroom furniture; a centrepiece of every bathroom.

Plumbworld has a huge range of bathroom vanity sinks, but there are considerable questions involved for buyers. How do you fit a vanity unit? What’s the process involved? Is it an all-in-one or can you select different parts for your basin?

Read on to learn not only what a bathroom vanity unit is, but how to fit one in your home, transforming your bathroom space…

What is a bathroom vanity unit?

A bathroom vanity unit is a vital part of your bathroom, combining a basin with storage space to create a sense of style and fantastic practicality.

Able to fit seamlessly into your space, a vanity sink can come in a variety of designs to suit every room size. Basin vanity units are among the most popular bathroom cabinets and can be wall-hung or extend from the floor upwards.

At Plumbworld, we stock a broad collection of styles, sizes, colours, and finishes to match every decor, whether it’s traditional or modern. These practical cabinets tuck away your toiletries and clear your cleaning products for a much less cluttered bathroom.

There is a vanity sink to suit every bathroom and can be tailored to your requirements, including drawers over cupboards, a double basin or combined with a toilet. These really are a must-have piece of bathroom furniture.

How do I fit a bathroom vanity unit?

Whether you or a plumber fit a vanity cabinet in your bathroom, it’s not as complicated as you might think.

Follow our five-step process below to remove your old sink and install a vanity basin…

Remove your old sink

First things first, take out your old sink. Remember to take your time rather than rushing in and ripping it away, causing damage to your flooring or pipes.

Before you do anything, switch off your main water supply and disconnect supply lines for hot and cold valves and basin waste - or trap. This will avoid things from getting very wet and messy - and potentially expensive through damage.

Once you’ve done this, you can remove your old basin.

A bathroom sink will, traditionally, be attached to the wall or floor with sealant or screws - particularly if part of an old vanity unit. There are two ways to remove sealant:

  1. Use a sharp razor blade or knife to carefully cut through it. It may also help to use a heat gun, or even a hairdryer, to apply heat to the sealant. This will then make the unit loose enough to be removed.
  2. You can also use sealant remover. This involves applying the remover - which is in liquid or spray form - and then cutting it away with a knife, like the above process.

Once this is done, slowly and carefully remove the old basin from the wall or floor.

Position your new basin

Measure your new basin, and then decide exactly where you want to position it. Once you’ve done this, mark it with a pencil as a guide.

Read more: Different Types of Bathroom Basins

The majority of vanity cabinets are open at the back; however, some may need holes to be drilled or cut to allow for the pipework to fit and be fed through. This makes positioning your cabinet so vital.

If you do need to drill holes in your cabinet, make sure you sand the holes down, so as not to catch and, potentially, damage the pipes.

Fitting your vanity cabinet unit

Once you’ve finished positioning your unit, it’s time to fit it. Firstly, align it in position using the pencil markings, making sure the cabinet is flat against the wall and not obstructed in any way.

Check to see that your pipes and holes, if you needed to drill them, line up correctly. If not, make any required adjustments. If everything matches up, you can begin to fit your vanity cabinet.

For a sturdy fit, locate the wall studs in your bathroom before screwing the vanity unit into place. Drill the screws into the studs and then fit the cabinet to the wall, making sure it’s securely attached. This is crucial before moving on to the basin.

Use a spirit-level to see whether the unit is level - this is vital before placing your basin on top - you don’t want everything off-balance.

Fitting the basin on your vanity cabinet

Before you fit the basin on top of your vanity unit, you need to attach your new taps and waste - this is easier than attaching the sink before the taps.

How do I install new taps?

1: Lower your new tap into the provided hole in the basin, making sure it stands at a 90-degree angle.

2: From below the tap hole, screw it in place with the provided nut.

3: If you are happy with the position, tighten the nut, making sure not to damage the basin while doing so.

If you are installing a hot and cold tap, repeat the process for a cold tap - a hot-water tap always goes on the left.

4: To connect your tap to the plumbing attached your tap to the copper piping; screw a connector into place if required. It may be best to leave this to a qualified professional.

Read more: Bathroom Taps Buying Guide

Once your taps are attached to the basin, you can align it on top of your vanity cabinet. Once this is done, use a spirit-level again to check everything is perfectly level.

If everything is level, you can move on to sealing - or bonding - your basin in place.

To do this, you’ll need sealant.

Apply your silicone sealant by squeezing it into the gap between the basin and vanity cabinet. By doing so, this will create a watertight seal, helping to prevent any water damage.

You will also need to apply sealant to the gap between your vanity cabinet and the bathroom wall. To do so, make sure your cabinet is pressed firmly against the wall, and then apply more sealant. This will create a secure and professional finish.

Sealant takes up to 24 hours to set, so, make sure your bathroom, or the sink, is off-limits for that amount of time.

Check the water supply and final tests

The final stage is to check everything works, making sure there are no leaks with your new vanity cabinet.

Once your sealant has dried, you’ll need to check all the connections are secure before switching on your water supply. Switch the main water supply back on and run the tap for a few minutes.

Check the connections between your tap, drain and pipework. If there are no leaks, everything is secure and flowing freely, you’ve successfully fitted your vanity unit!

If you found this post useful, you may also be interested in - Vanity Unit Buying Guide - How to Fit Bathroom Wall Panels - How to Fit a Bath Panel.


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