How to find your stopcock

Every time we get called to a burst, the first question is "where is your stopcock?" and the answer, more often than not, is "I do not know". By the time we have found it, a lot more water has gone into the house than needed to.

You have two of them. The internal stop tap inside the house is the one that matters in an emergency. There is also an external one out at the boundary, which is the water company's.

Where the internal one usually is

It is on the pipe that brings cold water into the house, so it is nearly always near where that pipe comes through the floor or wall. In rough order of likelihood:

• Under the kitchen sink, at the back, behind whatever is stored under there
• In the downstairs loo or utility room, often boxed in
• Under the stairs, or in the cupboard by the front door
• In the garage, if it is attached to the house
• Under a hatch in the hall floor, in older houses
• In the cellar, in Victorian terraces
• In the airing cupboard, occasionally, in flats

In a flat it may be in a communal cupboard on the landing, and there may be one for the whole block as well as one for your flat. Worth establishing which is which before you need to know.

What it looks like

Usually a brass tap with a small round wheel or a lever, sitting in the pipework rather than on the end of it. In newer houses it may be a plastic lever valve. Older ones can be crusted enough that they do not look like a tap at all.

Which way to turn it

Clockwise to close, the same as a tap. A lever type closes when the lever sits across the pipe rather than along it.

To check it has actually worked, close it and then run the cold tap at the kitchen sink. It should run for a few seconds and stop. If it keeps running, the stopcock has not closed properly.

Test it twice a year

This is the part people skip. A stopcock that has not been moved in fifteen years seizes solid, and you find that out at the exact moment you need it. Turn it off and back on every six months — when the clocks change is as good a reminder as any.

The external one

Out at the edge of your property — in the pavement, the verge or the front garden — there is a small metal or plastic cover, usually a few inches across and marked "W" or "Water". Under it is a deep, narrow chamber with the stopcock at the bottom, and often the meter.

It normally needs a long key to reach. It is worth knowing where yours is, but the internal one is the one to use in a hurry.

While you are down there

Two things worth doing at the same time. Put a label on the stopcock, so anybody in the house can find it. And take a photo of where it is on your phone — that is what you will actually look at when you are panicking.