My stopcock is leaking – help!

You might be able to stop your leaking stopcock or dripping stopcock with the right tools and effort. Just read this step-by-step advice to get your stopcock working perfectly again.

Before we move further, remember! Everyone with our plumbing and drainage cover service plans will receive a quick repair within 24 hours of the time they inform us that an internal stopcock is leaking, so if you’re an eligible member, give us a call on our 24/7 claims line. We will fix your stopcock efficiently and effectively.

Locate your stopcock

A stopcock, also known as a stop valve, will shut off your domestic water supply, minimising the damage a leak can cause.

If you don’t know where your stopcock is, check the following locations:

• Stopcocks are usually found in rooms with water outlets, such as kitchens and bathrooms.

• They are usually located on outside walls.

• Houses with internal water meters almost always have their stopcock installed on the pipe that leads to the water meter.

• Stopcocks are usually at knee height, although this is not always the case, especially in flats and apartments.

Turn off the water

Did you know you may be able to turn off your water supply even when your stopcock is seizing up? There should be a stop valve outside your home, on the boundary of your property. They are frequently on the pavement and have a clearly marked cover. If you have a water meter, your external stop valve might be in the same chamber as the meter.

If you cannot find the Water Authority’s stop valve, give your local water authority or your utilities supplier a phone call. Your neighbours may also know where it is.

Please note that this external stopcock could shut off your neighbours’ water supply as well as your own, so it is polite to let them know you intend to close it.

In some instances, these stop valves can only be closed with a universal stopcock key, which can be purchased from major DIY and home improvement stores. Turn the valve clockwise, and be careful—you don’t want to break this stopcock too!

Where is your stopcock leaking from?

Leaking compression nuts

The compression nuts are on either side of the stopcock and connect the stopcock to the plumbing supply.

• Try to tighten the nuts. Use water pump pliers to hold the tap around the head gear joint, and then turn the nuts clockwise with a spanner.

• If this doesn’t work, turn the leaking nut in an anti-clockwise direction to remove it. Then wrap the olive with PTFE tape and reassemble the stopcock. You will need to have turned the water supply off and drained your plumbing to do so.

Leaking head gear joint

The headgear joint is between the compression nuts and underneath the gland nut and the tap itself. One of the symptoms of a leaking head gear joint is a seized stop tap, i.e., you will be unable to turn the stop tap off fully.

To resolve this problem, you will need to replace the washer. Make sure you isolate the water supply at the stopcock and drain your pipes beforehand.

• Hold the stopcock with a pair of plies.

• Turn the nut in the middle of the stopcock underneath the tap in an anticlockwise direction with a spanner.

• Unscrew the handle from the rest of the tap.

• Remove the rubber washer at the end of the head gear joint and replace it with a new one.

• Wrap PTFE tape around the assembly.

• Reassemble the stopcock and tighten it back up with a spanner.

Leaking gland nuts

The gland nut connects the tap to the headgear joint.

• Try to tighten the gland nut. This can stop a lot of leaks.

• If this doesn’t work, hold the large nut on the head gear joint in place with a spanner, and use another spanner to undo the gland nut.

• Remove any packing from the gland nut with a screwdriver or any other long, slim device.

• Replace this packing with specialist packing bought at a DIY or home improvement store. Do not pack too tightly.

• Wrap the spindle with PTFE tape.

• Reassemble and re-tighten the stopcock.

Stopcock maintenance

Because of the damage a seized-up stopcock can cause in plumbing emergencies, it is a good idea to maintain your stopcock regularly.

• Please turn it off and on again every couple of months to keep the tap loose and prevent it from rusting up and becoming stiff.

• If you notice your stopcock is stiff, give it a spray with WD40.

• If it is still stiff, contact us – if you have plumbing and drainage cover, you can claim for seized stopcocks.

Still having trouble?

Contact us on 0345 3192 247 and we can help! Our technical teams will run through some simple troubleshooting tips with you to see if your problem can be resolved over the phone. If not, we’ll send a highly skilled and qualified plumber round to get your plumbing problems sorted as soon as possible.

There could be a number of reasons for your drainage issues, so it’s better to trust the professionals. After all, you could end up making it worse, and you could be faced with a hefty bill to pay to repair the damage. We help, we repair, and we care.