isolate water supply
If you are working on your house you may need to locate and isolate the water supply to your property.
The water supply to your house from the main water supply is via a pipe called the rising main. The rising main usually has a stopcock (shut-off point) outside the property and inside - usually under the sink.
Closing these is simple - they are typically simple valves which stop the flow of water when closed. To close a stopcock turn it clock wise, to re-open it, turn it anti-clockwise.
It is important to familiarise yourself with the location of these two stopcocks - when you have an emergency like a burst pipe, and water is flooding your house, is not the time to wonder where they are!
You can open the cover of the outside stopcock with a flat screwdriver, levering the cover upwards. The stopcock will be about 75 cms (2 feet 6 inches) below ground level.
It's quite possible it will be covered with water, sand or other debris - some people have even found used needles down there, so take care when reaching in. You will need a stopcock key to turn the water on and off, these can be bought for a few pounds from a DIY store.
Locations of external stopcocks vary widely - they can be at the front or the back of your property, while in old terraced houses, you may find that there is one stopcock at the end of the street which serves the whole street! Thus you will need to give your neighbours warning before turning off the water.
The stopcock under your kitchen sink should have plastic pipes connected to it - if you are in an older house, check to be sure - if the pipe is a dark grey metal, it could be lead. Lead pipe should be replaced as lead can damage your health.
You are responsible for pipes on your property, so you will have to arrange for and pay for any work required to the pipes there.