Stop Taps: Finding the Inside and Outside Valve

Your stop tap is the valve that shuts off the water supply to your home. Every property has one inside, and most have a second one outside near the boundary. In most homes the inside stop tap is under the kitchen sink, and you close it by turning it clockwise, which is the same direction as tightening a screw¹. It may take a few turns to stop the water, and a few minutes for the flow to stop altogether¹.

Knowing where this valve is and how to use it can save you from major water damage in an emergency, such as a leak or a burst pipe¹. It is also the first thing you need when carrying out plumbing or building work². The Met Office's advice for frozen and burst pipes is blunt on the point: "Make sure you know where your stop tap is and check it's working every six months"³.

This page covers where to find both valves, how to turn the water off and back on, what to do about a stiff or leaking stop tap, who owns which valve, and the extra complications of flats and shared supplies. If a pipe has already burst, see what to do if a pipe bursts for the full emergency steps.

What a stop tap is, and what it looks like

A stop tap, also called a stopcock or stop valve, is the point where you can shut off the water supply to your home¹. The Met Office uses the same three names in one breath: "It's also important to know where your stoptap (also called stopcock or stop valve) is"⁷. There are two types: internal stop taps, inside your home, and external stop taps, outside it⁶.

The inside stop tap is easy to recognise once you know what you are looking at. It looks like a spout-less tap or lever, and it sits between two lengths of pipe, acting as a connector¹. Rather than a spout pointing down into a sink, it has a brass or metal head with a handle, or a lever, in line with the pipework. Turning that handle or lever is what stops the water flowing past it into the rest of your house.

A typical property has both an inside stop tap, which is the responsibility of the owner or landlord, and an outside stop tap, which is usually the water company's⁸. The inside valve controls everything within your home. The outside valve controls the supply reaching your property from the main in the street, and it is the one to reach for if the inside tap is broken, seized or unreachable.

Finding your inside stop tap

Start under the kitchen sink. In a home, the inside stop tap is usually located there, because it sits just after the water pipe enters the house¹. Government guidance for Northern Ireland gives the same answer for the whole UK: know where the internal stop valve is, usually under the kitchen sink, and how to turn it off⁹.

Not every home keeps it there, so if it is not under the sink, work through the other common locations. WaterSafe, the national register of approved plumbers, lists utility rooms, downstairs cupboards and basements¹⁰. The Met Office adds downstairs bathrooms, kitchen cupboards, garages, cellars and under the stairs³. Northumbrian Water notes that some are in the bathroom or in the boiler cupboard¹¹. Richmond Council's utilities failure guidance gives another spot worth checking: under the floorboards by the front door, alongside the airing cupboard¹².

• Under the kitchen sink, or inside a kitchen cupboard⁶
• Downstairs bathroom, toilet or cloakroom³
• Garage or utility room¹⁰
• Cellar or basement¹⁰
• Under the stairs³
• Airing cupboard or under the floorboards by the front door¹²

The rule of thumb behind all of these: the stop tap sits close to where the water pipe enters the building². If you are hunting for it, think about which outside wall your supply most likely comes through, often the kitchen wall nearest the street, and search the rooms and cupboards on the other side of it.

If you cannot find it at all, contact a plumber, who can attempt to locate it or advise you of other options for turning off your water supply internally¹³. Your water company may also help: Affinity Water, for example, offers an online form and will get in touch if you still cannot find your stop tap¹⁴.

Turning the water off, and back on again

Turning the tap is simple, and the direction is the same for standard water fittings everywhere: clockwise to close, anti-clockwise to open¹³. Affinity Water's instruction is typical: "Turn the stop tap clockwise (to the right) to turn the water off, and anticlockwise (to the left) to turn it on"⁴.

To shut off your water:

1. Turn the stop tap clockwise, to the right. It may take a few turns to stop the water².
2. Wait. It may take a few minutes for the water to stop altogether, as the water already in your pipes drains out through open taps¹.
3. To turn the water back on, turn the valve anti-clockwise, slowly¹.

Two cautions apply. First, go slowly and never force it. WaterSafe warns: "Turn it on and off slowly, never force it. If you over tighten or use excessive force you may damage the stop tap"¹. Second, some stop taps only need a quarter turn. Affinity Water advises: "Go carefully, as some of our stop taps only require a quarter turn, don't over tighten them"¹⁵. If the handle stops turning, it has done its job; wrenching it further can damage the valve and leave you with a leak at the very fitting you depend on in an emergency.

Clearing airlocks when the water comes back on

After you turn the supply back on, taps may splutter or run weakly because air is trapped in the pipes. South Staffs Water gives a simple method for freeing it: turn on the cold tap nearest to the stop tap, then carefully turn the stop tap anti-clockwise to open and clockwise to turn off, a few times. This should free any airlocks or blockages in the pipes¹⁶. Run the taps until the water flows steadily and quietly.

If the problem persists, or if no water comes through at all, the valve may not be fully open. Richmond Council's guidance for water supply failures is to check your inside stop valve is fully open and turn it anti-clockwise to ensure it is¹². Beyond that, contact a plumber.

The outside stop tap: under a small cover in the pavement

The outside stop tap is found outside, near the boundary of your property, under a small cover about the size of a CD case⁵. Wessex Water lists the places to look: a meter chamber, the footpath or verge, under a plastic or metal cover¹⁷. South West Water says its external stop taps are typically located under covers in the footpath or pavement⁶. If you have a water meter, the outside stop tap will generally be in the same pit or chamber as the meter⁵.

To operate it, the direction is the same as inside: turn the valve clockwise to close, anti-clockwise to open⁵. Some external valves have a plastic lever rather than a metal head. If it appears to be made of a plastic type material, it may only require a quarter of a turn to turn off the water. When the lever is in line with the pipe the supply is on; when it is across the pipe, the supply is off⁵.

Meter covers and specialist keys

Some water meter housings need a specialist key to open, and if the stop tap is not in the meter box you will need to contact your water supplier⁵. Do not force a cover that will not lift. If you cannot find your outside stop valve at all, WaterSafe's advice is to contact your local water supplier, who can help locate it¹⁸. Not all properties will have an outside stop valve fitted, and this is quite common in older homes, or where the incoming water supply serves both your home and one or more of your neighbours¹⁸.

When to leave the outside tap to a plumber or the water company

The outside stop tap is the water company's valve, and it should be treated differently from the one under your sink. WaterSafe is clear: "Ideally it should only be used by a qualified plumber or by the water supplier"¹⁹. The same register warns that not all water suppliers will give permission to use the external stop tap, and that if you operate it and damage it, you may be liable for the repairs¹⁹.

So the outside stop tap is a backstop, not your first move. Use the inside tap for anything inside your home. Reach for the outside valve when the inside one is broken, seized or will not shut off the flow, and if you can, have a plumber do it or call your water company first¹⁹. If your plumber cannot operate the external stop tap, or you cannot locate it, contact your local water supplier²⁰.

One check comes before any of this. Affinity Water advises: "Before you turn off your external stop tap, check that you're not on a shared supply, that is, one stop tap serving more than one property"²¹.

Shared supplies, flats and terraces

In older terraced properties, one outside stop tap can sometimes control the water supply of several properties¹⁷. If your supply is shared, the outside stop tap could be outside your property or further along the street, and using it could also turn off your neighbours' water². On a shared supply, turning off the external stop tap shuts off water to every property on that same supply, so let your neighbours know first²⁰.

Flats have their own arrangement. A communal stop tap will generally be found where the water supply enters the building, and an additional stop tap should also be found where the water supply enters your individual flat². The one inside your flat is the one to use for work or an emergency in your home; the communal one affects every flat in the block.

Who is responsible for each stop tap

The split is straightforward, and it is the same principle across water companies. The external stop tap is usually the water company's responsibility, while the internal stop tap is yours to maintain⁶. Cambridge Water puts it plainly: the owner or landlord of the property is responsible for all inside stop taps².

South Staffs Water gives the boundary in more detail. It is responsible for stop taps located outside the boundary of a property, which includes the outside stop tap usually found in the road or footpath. All stop taps located either in your garden or inside your house are the property owner's⁸.

The Drinking Water Inspectorate, the regulator for water quality in England and Wales, extends the same logic to the pipework: the part of the service pipe leading from the stop valve outside your property to the point where it enters your home is the owner's responsibility, as is all plumbing inside the home to the kitchen tap²⁴.

If you are a tenant and do not know where your main stop tap is, your landlord should be able to help you¹¹. Report a leaking or seized valve to your landlord promptly: it is their fitting to maintain, but a flood damages your home first.

A stiff, stuck or leaking stop tap

Stop taps that are never used seize up, which is exactly why the six-monthly check matters. If your internal stop tap is not turning or shutting off, you will need to contact a plumber to fix this¹. Cambridge Water's advice is the same: if you are having problems operating your inside stop tap, contact an approved plumber². Do not force it, and do not work on fragile or corroded pipework around it yourself²².

If you cannot turn the water off at all, the outside stop tap is the fallback, used ideally by a qualified plumber or the water supplier¹⁹. If neither valve works, your water supplier is the call to make.

Water leaking around the stop tap itself is a common fault with a simple cause. Water around the joints is usually caused by loose or worn nuts and seals²². It is not a plumbing job for an emergency attempt at home: turn the supply off if you can, and get a plumber, who can replace the washers or the valve. While you wait, a leaking stop tap is one more reason to know where your outside valve is.

Check your stop tap works every six months

The Met Office's winter advice is to check your stop tap is working every six months³. North Wales Fire and Rescue Service, writing on ice and burst pipes, says the same: make sure you know where your stop tap is and check regularly that you can turn it off easily in an emergency²⁵. Affinity Water suggests turning it on and off two to three times a year⁴.

The check takes a minute:

1. Find the tap and clear anything stacked in front of it.
2. Turn it clockwise until the water stops running at a tap.
3. Turn it anti-clockwise to open it again, slowly.
4. If it will not turn, or it leaks when you move it, book a plumber now, not during the next cold snap.

Two habits make the valve easier to live with. First, keep the cupboard under the sink clear enough to reach the tap in a hurry, with a torch nearby if the cupboard is dark. Second, label it. The Met Office suggests making your stop tap easy to find in a plumbing emergency by tagging it with a spare gift label carrying the number of a WaterSafe registered plumber¹⁰. Anyone in the house, including a babysitter or a visitor, can then shut off the water without hunting for you first.

While you are at it: the gas valve and the fuse box

The stop tap belongs to a set of three shut-off points every household should be able to find in the dark. Greater Manchester's resilience guidance lists knowing your water stop tap, where the water supply comes into your home or outside near the property's boundary, alongside the same preparation for gas and electricity²⁶. The gas shut-off is at the meter, and the electricity is isolated at the consumer unit or fuse box.

If you are mapping all three for your household, the getting started guide walks through them together, and the home emergencies guide covers what to do when each one fails. For the water side specifically, see frozen pipes, burst pipes and water leaks on your property.