How to Turn Off a Water Supply

If you are dealing with a drainage problem or carrying out DIY work that could impact your home’s pipes and drains, it is important that you know how to turn off the water supply before you get started. Failing to switch the water off before carrying out this work could result in water leaking everywhere and flooding your home.

There are various reasons why you might need to switch off your home’s water supply; whether you are repairing a leaking pipe, installing a new kitchen sink or bathroom taps, or fixing a problem with your central heating system or utilities. However, if you have never done this before, you may not know where your stop tap is located, or which shutoff valve you should use.

Here, the drainage experts at Lanes Group will explain how to find your stop valve and turn off the water supply – so you’ll know what to do when the time comes.

Turning off the water supply to a specific fixture or appliance

If you are experiencing a localised problem with a burst pipe or a leak affecting a single specific appliance – such as a sink, toilet, shower, radiator or washing machine – you will usually be able to switch off the water supply to this specific fixture by finding the relevant cutoff valve or isolation valve.

In most cases, this will be a simple valve attached to the pipe system connecting to the appliance or fixture in question; in the case of sinks and showers, there will usually be two valves, allowing the hot water supply and cold water supply to be controlled and cut off separately. If you are having a problem with the sink or need to make major repairs, it will usually be necessary to switch off the hot and cold water pipes at the same time.

In order to shut off the water, all you will need to do is turn the valve clockwise. When operating any shutoff valves, it’s important to remember not to apply excessive force, as this could damage or jam the stop tap and create further problems.

Once you have switched the water supply off, you should run the hot and cold water taps connected to the valve in question until all of the water has drained from the pipes. When the pipes are empty, it will be safe to make repairs.

Turning off the main shutoff valve for your home

If you are experiencing a larger problem with your plumbing or drainage – or need to carry out major DIY work that might affect the entire house – then the safest thing to do is find the main stopcock or property shutoff valve.

This central stop tap controls the water supply to every fixture and appliance in the home, and should be your first port of call if you are having a non-localised plumbing problem, or if you simply need to shut everything down quickly in case of an emergency. There are actually two valves controlling your water supply, with one located indoors and the other outside – your internal stop tap will usually be the first option.

You will usually be able to find the main internal stop tap in one of the following locations:

• Underneath the kitchen sink
• In an airing cupboard or utility room
• In a downstairs bathroom
• In the basement
• Under the stairs

Once you have found the internal stop tap, simply turn the valve clockwise to turn off your water supply for the whole home. You should then leave the hot water and cold water taps running to drain the remaining water from the pipes before getting to work.

Turning off your water supply via the street shutoff valve

If the internal stop tap is damaged or inaccessible for any reason, you also have the option of using the external street-level shutoff valve to turn off the water supply. This will be located outside your property, near to the property boundary, in one of the following locations:

• On or near the road, pavement or driveway in front of your home
• In the same pit or chamber as your water meter
• In the soil or grass at the end of your garden, or the grass verge at the front of the property
• At the end of your road, if you and your neighbours have a shared supply pipe

This main property water shutoff valve will be placed under a small plastic or metal cover, about the same size as a CD case, and will need to be accessed with a screwdriver. You should turn it clockwise to shut the water off.

You should remember that the external stop valve should only be used when there are no other options; in some cases, you might need permission from your local water company to use the valve. The external stop tap will often connect to multiple homes, so switching it off will turn the water supply off for your neighbours as well – they will need to be notified.

For more information, take a look at our guide on how to find and use your external stopcock.

Getting help with your plumbing or drainage emergency

Once you have successfully turned off the water supply to your home, or to the relevant appliance, you will be able to safely carry out the necessary plumbing repairs without running the risk of further flooding or damage to the property.

If you have the right tools and DIY expertise, or if the situation requires only minor plumbing adjustments, you may be able to carry out the relevant work by yourself. However, if you are facing a major plumbing emergency or a serious fault with your drains, it is always best to call in a professional.

Problems with your water main or water supply pipes should be dealt with by a licensed plumber. If the problem is with your drainage system, then Lanes Group is here to help.

Find out more about our domestic drain repair and relining services here, or give us a call on 0800 526 488 to learn more.