How To Find Your Outside Stopcock
You must know what to do in an emergency to ensure that your home’s plumbing and drainage systems remain in good working order.
If you experience a leak or a burst pipe, you must be able to quickly turn off the main water supply to prevent flooding or water damage.
To do this, you must know the location of your property’s stop taps, also known as stopcocks.
In this article, you’ll learn what a water stopcock is and how to locate your stopcock in case anything goes wrong.
If you would also like to find out where your drains are, you can read our article ‘How to find out where the drains are on my property’.
What is a stopcock?
A stopcock is a valve that controls the supply of water into your home, and can be used to shut the supply off at the source if you have a major leak.
There are two types of stopcocks: the internal one, which is located inside your property and controls the water flow within your house and the external one, which is found outside the property and controls the property's main water supply.
Where is your external stop tap located?
Because external stop taps are located outside the home, they can be more difficult to find than the internal stop tap, which can reliably be found under the kitchen sink, stairs, airing cupboard or utility room, or downstairs toilet.
By contrast, you may need to search for your external stop tap, located outside the front of your property, near the property boundary.
It could be in any of the following common locations:
- On or near the road in front of your home
- In the same pit or chamber as your water meter
- In the soil or grass at the end of your garden, or on the adjacent pavement
- Embedded into the grass verge at the front of the property
- At the end of your driveway
- At the end of your road, if you and your neighbours have a shared supply pipe
What does your external water stop tap look like?
You will be able to recognise the external stop tap from the small plastic or metal cover, about the same size as a CD case, which will usually be marked with text saying “WATER”, “STOPCOCK”, or simply the letter “W”.
It is important to know how to find your external stop tap before a water leak occurs, so if you do not know where it is, it could be a good idea to search for it and note its location for when an emergency arises.
How to shut off your external water main valve
It is important to note that you should use your inside stop valve in most cases where you need to switch off your cold water supply. However, if the internal stop tap cannot be accessed for some reason - or if you have a leak in the supply pipe between the inside and outside stop valves - then using the external valve may be necessary.
In these cases, follow these steps:
- Open up the stopcock cover using a flathead screwdriver
- Use a torch to assist you in locating the valve within the chamber if necessary
- Turn the stop tap clockwise using either your screwdriver or a dedicated stop tap key, depending on the design of the valve. If you need a stop tap key, you can purchase one from a DIY or hardware store
- Stop turning the valve when it can no longer be turned, and wait for all of the water to run out of your taps
Who is responsible for the external stopcock?
Your external stop tap's responsibility and liability will depend on where it is located. If it is within the property boundary, it is your responsibility to maintain and operate the valve when necessary, including repairing the valve if it becomes damaged.
If the stop tap is located outside of the property boundary, then it is the responsibility of your local water company. In these cases, you may need to seek permission to operate the external stopcock, even in an emergency – this is because, for many properties, a single stop tap will connect to multiple homes, and switching it off will also turn the water supply off for your neighbours.
If your external stopcock falls under the water company’s jurisdiction, you may also need to seek permission to turn the supply back on after it has been switched off. The supplier will be responsible for maintenance and repairs, but if you operate the external stopcock and damage the valve, you may still be liable for the costs.
Because of these complications associated with using the outside stop tap, it is recommended that you use the internal stopcock in most instances.
Learn more about your responsibility as a homeowner in our article ‘Private drains and sewers’.
Who should I call for help?
If you are having trouble locating the external stopcock or want to know whether you have permission to operate it in an emergency, you should contact your water supplier to see if they can help you.
Once you have successfully located the external or internal stopcock and used it to turn the water supply off, you should contact a service provider who can help you fix the underlying problem with your pipes.
If the issue is with your water main or water supply pipes, you should contact expert plumbers; if the problem is with your drainage system, then Lanes Drainage Services UK is here to help.
Find out more about our domestic drain repair and relining services online, or call us on 0800 526 488 to learn more.