How to Install Water Shut-Off Valve Under Your Sink

A water shut-off valve is a great way to eliminate the need for turning the mains supply on and off – but can you install one by yourself?

If you live in a property more than thirty years old, or you simply haven’t got round to upgrading most of your plumbing equipment, then you might find that currently, whenever there is a bit of a DIY work that needs doing – be it a simple unblocking of a u-bend or the fixing of a leaky tap – you constantly need to be turning off the water supply at the mains before getting started. And not only is that a chore in itself, but it also means that water throughout the entire property is completely shut off for the duration of the job. So how can you get around this? Well, why not look into installing a water shut-off valve (also known as a compression shut-off valve)  under every sink?

Benefits of a Water Shut-Off Valve

There are numerous benefits to having water shut-off valves installed across your property, as these modern devices can help you to carry out a quick DIY repair job in almost half the time. They also:

• Function as small screw-on addition taps that can be turned on or off by almost any member of the family.
• Cut off the water supply to a single sink without affecting the water supply in the rest of the home.
• Reduce the risk of flooding or severe flood damage by enabling you to shut off the water almost instantaneously.
• Can be found in almost any DIY or hardware store across the UK, and for a relatively small price compared to most fixtures and fittings!

Installing a Water Shut-Off Valve

What will you need 

To help you get started, we’ve come up with the following step-by-step guide to installing a water shut-off valve under your sink. Once you’ve bought the valve all you need is access to the supply pipe; a new supply line; a pipe cutter; a spanner; and a few screws and waterproof Teflon tape. If you have everything you need then you’re ready to get started!

1. It’s a little ironic considering the purpose of the DIY job, but the first thing you need to do is shut off the water supply at the mains (remember, this is what you are aiming to stop doing once the valve has been fitted!)
2. Next, locate and disconnect the old supply line. Hopefully this will involve just unscrewing the piping, but if it is soldered together you might need to make use of the pipe cutter at this stage.
3. Once the supply line is exposed, slide the compression nut from the shut off valve onto the pipe, followed by the ring that secures it in place. Wrap these around the pipe using Teflon tape, and the push the shut off valve onto the pipe too, tightening it with the spanner before continuing.
4. Now you are ready to attach the compression fitting of the flexible supply tube to the other side of the pipe and tighten next to the valve.
5. Then, hook the flexible supply tube onto the base or underside of the tap, and hand tighten this into place. Take care not to over-tighten the fittings, as this can constrict the flow of water once you’re finished.
6. Finally, once everything is securely in place, you can turn the water on again and check for leaks – if it runs smoothly, you can double-check the valve actually works – and you’re done!

Useful Tips

• Make sure you know where are you going to install the shutoffs.
• The water supply is usually located close to the water meter.
• After shutting the water off, open a faucet on the lower level of your home and let the water lines run until it is completely drained.
• It is also important to know the distance to the base of the faucet to install, in order to purchase the right length of supply line.
• Find how your supply lines connect to your sink (floor or sink).
• If the plumbing comes up through the floor, you should install straight valves.
• If the water pipes come from behind the wall, you could install either a straight shut off valve or an angled one, depending on the vertical run of the supply line.
• When all the work has been completed, do not forget to turn on the water supply again before using the faucet.

While this may sound easy enough to some, not everyone is comfortable playing around with piping and water connections; and if this doesn’t sound like the sort of job for you then you can always hire a trained and experienced plumber to come and do the installation for you. It may be a bit of extra expense, but they should manage to get the job finished in a matter of minutes – saving you a lot of time and hassle!