Ask any (reputable) plumber in Guildford, before we start any work we make sure we can turn the water off. In this post I will describe the three most commonly found stopcocks in the UK home.

Typical mains stopcock

Locating the main water supply

You should know where you mains stopcock is, this is the main water supply which comes from underground, to your property.

It’s normally under the kitchen sink or in a cupboard somewhere on the ground level of your property.

It’s a good idea to spray the stopcock with a little WD40 every now and again, and then open and close it as they can seize up. In an emergency you want to be able to turn the water supply off as quickly as possible, to reduce damage to your property so making sure you know where it is and that it functions properly is crucial.

If this valve has seized up, the water will need to be turned off in the road so that the old stopcock can be replaced which you may not be able to do quickly and this is a job for a professional.

If you are having problems call Surrey Heating Services on 01483 871871


Turning off the hot and cold supplies to the bathroom

Typical Gate Valve

If you have a traditional plumbing system, i.e. have a hot water cylinder and cold storage tanks in the loft, you may find that, even though the mains stopcock has been turned off, you still get cold water out of your bath and basin taps and your toilet cistern will still fill.

This is because the cold water storage tank in the roof is full and you will need to either run the water in the bath until the tank is empty or find the gate valve to isolate the supply.

Gate valves will be located either in the loft, next to the tank, or in the airing cupboard.

There will be one gate valve on the pipe that connects to the bottom of the hot water cylinder, turning this off will stop the supply of hot water to the whole property. The other will be a cold supply to the bathrooms.

Do not over tighten these valves as the spindle inside may snap which will mean replacing the valve!!






Sometimes you won’t need to turn off the supply to the entire property, as it is now common to find each supply has been fitted with a individual isolator, called a Ballofix valve, which can be simply turned off using a flat bladed screwdriver.

In the picture below, this valve is in the on position. By turning the screw, in the valve, a quarter of a turn you will stem the flow of water.

Ballofix Valve