Old brass tap and valve body on a wall with a drip of water

Stop tap and water shut off in London

Stop tap help: when you cannot turn the water off

Your stop tap, also called a stopcock or stop valve, is usually under the kitchen sink, in an airing cupboard, under the stairs or near the front door. Turn it clockwise to close. If it is stuck, missing or leaking, use the isolation valves near the leak or the outside stop tap, then get it repaired or replaced.

Is it an emergency?

Photo for illustration

Stop tap and water shut off: tap what is happening

You see what to do right now, then send it through.

01Right now
02Your home
03Call back

Step 1

Right now

What is happening right now?

You need this when

If any of these is happening now, turn the water off at the stop tap first.

Stop tap and water shut off

You cannot find your stop tap
The stop tap will not turn, or turns but the water keeps running
The stop tap is dripping or leaking from the spindle
Your flat seems to have no stop tap of its own
Turning off your stop tap also cuts water to the neighbours

Step by step

What happens from the first message to the written note at the end.

1
Shut the water off another way
If the main stop tap has failed, we isolate the supply at the outside stop tap or a communal valve, with the neighbours told if it is shared.
2
Assess the valve
Some valves just need the spindle freed or a new washer. Others are too scaled or corroded and should be replaced.
3
Repair or replace
We fit a new stop tap where it can be reached easily, and add isolation valves on key appliances if you want them.
4
Show you how to use it
We show everyone in the household where it is and how to close it, and label it if that helps.

Where to find the stop tap in a London home

Thames Water says the inside stop valve is usually just after the water pipe enters the home: under the kitchen sink, in an airing cupboard, under the stairs, under the floorboards, near the front door, or in a garage, utility room, bathroom or cellar.

Flats are harder. Thames Water notes you may have a communal inside stop valve where the supply enters the building, and sometimes another where the supply enters your flat. In a Victorian conversion, the valve for the top flat may be in the hallway of the ground floor flat, or in the cellar. In mansion blocks it may be in a riser cupboard on the landing. If you rent, ask your landlord or agent where it is before you need it.

Why stop taps seize in London

A stop tap that is never used gets stiff. London's hard water makes it worse, because limescale builds up around the spindle and the washer. Thames Water recommends checking your inside stop valve every month so you know it works.

If yours will not turn, do not force it with a long wrench or a hammer. Old brass valves can snap at the body, which turns a stuck valve into a burst. A little careful back and forth movement sometimes frees it. If not, use another way to isolate the water and have it replaced.

The outside stop tap and shared supplies

The outside stop valve is usually under a small cover in the path or pavement. Thames Water says it should only be used in an emergency, may need a stopcock key, and, if your home is on a shared supply, will turn off the neighbours too. In older London streets it can be at the end of the road.

If neither the inside nor the outside valve works, Thames Water's advice is to contact a plumber. A plumber can also freeze a short section of pipe to stop the flow while a new stop tap is fitted.

Who fixes it, and making it easier next time

If your stop tap is under floorboards or behind a kitchen plinth, you can have it moved or have an extra valve fitted somewhere you can reach. Isolation valves on the pipes to the washing machine, dishwasher, toilet and basins let you turn off one appliance without shutting off the whole flat.

If you rent, the stop tap is part of the water supply installation your landlord must keep in repair under section 11 of the Landlord and Tenant Act 1985. Report a stuck or leaking one in writing, because it matters on the night something bursts. If you own a leasehold flat, the valve serving only your flat is usually yours, while a communal stop valve or the main valve for the building is usually the freeholder's. Ask your managing agent where the communal valve is and who holds the key to the room it is in.

No prices online

Every job is priced after a look at it, by photo or a visit, and agreed before work starts.

What affects the price

The cost depends on whether the valve can be freed or needs replacing, how easy it is to reach, and whether the water can be shut off elsewhere while the work is done.

What	Price
Freeing or rewashering a stiff stop tap	price confirmed after a look at the job
Replacing an accessible stop tap	price confirmed after a look at the job
Moving a stop tap or adding a valve	quote on survey
Valve in a shared or communal position	quote on survey

No prices are shown on this site. Every job is priced after a look at it, by photo or a visit.

Asked questions

Which way do I turn a stop tap to turn the water off?

Clockwise to close, anticlockwise to open. It can take a few turns and a few minutes for the taps to stop running.

Who is responsible for my stop tap?

Thames Water says the inside stop valve is the homeowner's to install, maintain, fix and replace. A communal valve in a block is usually the building's.

Can I turn off the outside stop tap myself?

In an emergency, yes, with a stopcock key. If the supply is shared, warn the neighbours first because their water will go off too.

My stop tap leaks when I turn it. Is that urgent?

A drip from the spindle is often a worn gland and can be booked in. A steady leak, or one from the body of the valve, needs looking at soon.