Finding your stopcock before you need it

Find it on a quiet afternoon, not at midnight with water coming through a ceiling. In most Edinburgh flats a torch and an empty cupboard are all it takes.

There are two valves with similar names, and only one of them is yours.

Which valve is yours?

The one inside your flat. Scottish Water's pipework guide separates the stop valve, which is inside the home and the homeowner's, from the stopcock at or near the boundary, which Scottish Water owns up to and including the stopcock. In other words, Scottish Water uses "stopcock" for its own valve outside, at the boundary, and "stop valve" for the one inside the home. Most people call the inside one "the stopcock" anyway, so this page uses "stop valve" for the one in your flat; leave the outside stopcock to Scottish Water.

Where do you look first?

Under the kitchen sink. Scottish Water says the stop valve is usually located under a sink, normally your kitchen sink. Empty the cupboard and follow the cold pipe that feeds the kitchen tap back towards the wall or floor. The valve is usually a small tap-like handle or a lever on that pipe.

Its frozen and burst pipes advice adds two more places: in a garage or near the hot water system. In a tenement there's no garage, so check the airing cupboard or wherever the hot water cylinder or boiler sits.

What if it isn't in the flat at all?

Then it may be where the supply enters the building. Scottish Water adds that a flat's supply is often shared, with the stop valve where the pipe comes into the building. In a stair in Leith or Bruntsfield, that can mean one valve controls several flats. Treat that as shared: ask your factor or neighbours, and don't close it without warning the other flats.

1. 1Look under the kitchen sink first
2. 2Check near the hot water cylinder or boiler
3. 3Check where the supply enters the building
4. 4Turn clockwise to close
5. 5Turn anticlockwise to open fully

Which way does it turn?

Clockwise to close. Scottish Water's burst pipe advice says the stop valve normally closes by turning clockwise. It turns anticlockwise to open, and its pressure factsheet says to make sure it is fully open if your flow seems weak.

If an old valve won't move by hand, leave it and ask a plumber rather than forcing it.

Why test it now?

Because a stuck valve is no use in an emergency. Close it, check the kitchen cold tap stops, then open it fully again. After any work on the supply, Scottish Water says a trickle can be air or sediment trapped in the internal stop valve, and suggests opening and closing it. It also says planned interruptions come with at least 48 hours' notice and can last up to 12 hours.

Can the pipe at the stop valve tell you anything?

Yes, it can show lead. The Drinking Water Quality Regulator says to look at the pipework under the kitchen sink: lead is dull grey, scratches to shiny silver and has slight bulges at the joints. It adds that homes built before 1970 are the most likely to have had lead supply pipes. If that sounds like yours, read lead pipes in Edinburgh.

Asked on the stair

Should you label the stop valve once you've found it?

It helps. A tag on the pipe saves the next person, or a neighbour helping out in an emergency, from searching the cupboard.

Does shutting the stop valve stop the hot water too?

It stops fresh cold water coming in. Scottish Water's burst advice then says to switch off the boiler or immersion heater and open the taps to drain the system; see burst pipe first steps.

Why does the kitchen tap still run after the valve is shut?

If the kitchen tap keeps running, the valve may not be fully shut, or it may be the wrong one; ask a plumber to check. In an older indirect system (Scottish Water links these to homes from before 1989), the kitchen tap is fed directly by mains pressure while other taps can keep running for a while from a cistern.

Can you replace the stop valve yourself?

It is your valve, but the supply pipe beyond it may be shared, and Scottish Water points people to a licensed plumber for internal pipework.

Where this comes from

1. Your guide to water pipework — Scottish Water (archived copy of its page): stop valve and stopcock
2. Advice on frozen or burst pipes — Scottish Water (archived copy of its page): where to look, clockwise to close, flats
3. Water supply FAQs — Scottish Water (archived copy of its page): trickle after work, planned interruptions
4. Your water pressure explained — Scottish Water (archived copy of its page): fully open, indirect systems
5. Lead in drinking water — Drinking Water Quality Regulator: how lead looks, pre-1970 homes