We all know that feeling, you look at your bathroom suite and think that it looks tatty or is in that 1970’s avocado colour. This article gives you some tips on how to replace the washbasin, further articles will cover replacing a bath and replacing the w.c.

Although it may seem surprising, replacing a wash basin only requires basic plumbing skills although it is recommended that the final work is checked by a plumber or electrician to make sure that any metal pipework is earthed correctly.

Before doing any plumbing work it is essential that the water is turned off at the mains and in a house with a tank in the roof that the tank is drained down (many modern houses do not have a tank in the loft with all water coming direct from the mains supply).

The steps to be taken to ensure that you are not going to be flooded when you take the old sink out are: –

  • Turn off the main supply coming into the house at the stopcock (you do know where that is don’t you?).
  • Close the valve on the cold feed to the hot water cylinder
  • Switch off the boiler, central heating and immersion heater
  • Turn off the valve from the cold water cistern to the taps (if you have a tank in the loft)
  • Turn on the bath and sink taps to drain the system (both the hot and cold water needs to be drained).

There are many different types of wash basin that you can choose from, including one that fit into the corner, hang on the wall, fit on top of a pedestal or even fit into the top of a cupboard. The choice of basin and depend on several factors:-

  • Where it will be used – corner basins are normally found in smaller downstairs WCs. Where as, wall hung and pedestal basins are normally found in bigger bathrooms.
  • What will look best
  • Will the wall support a wall hung basin (is the wall made of brick or plasterboard).

It is easiest to start by fitting the new taps to the new washbasin before it is fitted to the wall or pedestal as this will save the fiddling around behind the basin in a confined space with the risk of grazed knuckles or worse. Remove the back nut and washer from the tap tails, you need to make a note on which sides the hot and cold taps are on the old basin and push the right new tap through the correct holes in the new basin.

Replace the washers and the back nuts and tighten the nuts with a spanner, don’t forget to check that the taps are facing the right way before tightening the nuts. Then screw a flexible plumbing tap connector to each tail ready to connect them to the water supply.

Fit the new plug hole to the basin by smearing silicone sealant(or plumbers putty) over the top edge of the hole. Wrap PTFE tape in an anti-clock-wise direction around the threaded tail of the waste outlet fitting, the push the fitting into the top of the hole, bedding it down into the silicon sealant.

Turn the basin upside down and secure the waste outlet by screwing on the fixing nut. Attach a bottle trap to the end of the outlet fitting. Turn the basin back up the right way and carefully remove any excess silicon from around the waste outlet and then fit the plug and chain to the sink.

Now it’s time to remove the old washbasin. Make sure that you have some old towels or clothes before you start this as there will be a small amount of water in the u-bend or bottle trap that you are about to remove. Loosen the compression nuts on the tap tails of the old basin and then unscrew the old trap from the waste pipe – as we have already mentioned there may be a small spillage of water from the old trap, if there is mop it up with the cloth or a sponge. Finally, lift the old basin off the wall by unscrewing the fixing brackets or screws – it helps if you can have someone hold the basin while you are doing this to stop it falling.

If you are fitting a pedestal basin follow the manufacturers instructions for fitting this. Attach the new wash basin to the wall using suitable fixings.

Join the flexible connectors on the tap tails to the water supply pipes using PTFE tap to seal the joints, then connect the outlet at the bottom of the bottle trap to the waste pipe that leads towards the drains.

Finally, turn the water supply back on and carefully check all the joints, tighten up any leaking joints with a spanner. Cover the joint between the edge of the basin and the wall with waterproof silicon sealant in the colour that you want.

That’s it, you now have a new washbasin.


This article is intended as a basic guide only. Before starting, you must decide whether you can do the work without professional help. If you have any doubt about your ability we recommend you consult a professional plumber.