Leaking Stopcock In Airing Cupboard

[Booldawg]

More of a 'how much will it cost a plumber to sort' kind of question really as I wont be tackling this one myself?

The stopcock that sits between the cold water tank in the loft and supplies cold water to the bathroom is dripping slightly (about 400ml in a 48 hour period).

I've got a jug underneath it so its not an emergency (unless it gets worse)

I'm guessing its a washer, but also guessing the cold water tank in the loft will have to be drained and the inline stopcock removed from the piping?

How much as an estimate would this cost a plumber to do?

[Buenchico]

Unscrew the gland nut. Wrap some PTFE tape (from B&Q, or similar) around and push it down. Screw the gland nut up again. Time taken = a couple of minutes.

A plumber should only charge you his/her basic call-out fee but that might be fifty quid (or even more) for some plumbers. Ask for a quote first or simply do it yourself!

https://www.youtube.com/watch?v=H9b1AxSxbgw

[alavahalf]

Assuming the leak is coming from the spindle it's a fairly simple job as can be seen in the video .. if the leak doesn't stop at the first attempt, just unscrew the gland nut again and add another length of PTFE and pack it in before re tightening the nut.
If the leak is from either end of the tap compression fittings that's another matter and you may well need a plumber if this is the case. It's basicaly the same procedure, but the mains would need to be turned off. Still no big deal though.

[Togo]

Is it dripping from inside or is it condensation? Cold exposed pipes sometimes drip in warm weather. Otherwise close the external water supply stop tap (usually outside under a little metal cover) and drain down the system Make sure your gas boiler or electric immersion heater is off. You can then work on the valve. Usually a washer.

[Booldawg]

Thanks all, will check out the YT video.

Its definitely a leak. I'd replaced the feed hose to my toilet cistern and had to turn this stop cock on and off. It was after doing that it started leaking. Mustve disturbed a faulty washer that was only working due to inaction!

[alavahalf]

You have to ignore any information about it being a faulty washer .. how can a washer have any effect within a tap that is always in the open position.
If the washer in a stopcock leaked, you would never be aware of it. Think about it, the washer is contained inside the tap body and if it leaked, it could only leak into the main supply pipe.
Now you have added that little snippet about it leaking after you tampered with the cistern feed, it's obvious what has happened.
Stopcocks have a habit of leaking through the spindle.. ever so slightly.. and
when this happens they usually seal themselves up with calcium which is present in the water. They will sit there happily, often for years on end and never leak again due to the calcified ring that has formed around the spindle..( It is a green/white chalky substance often damp. Green comes from the copper pipe and white from the chalk)
So it's a simple DIY fix in 2 minutes. If you replaced your cistern feed, then you can easily do this. Watch the video shown above in Buenchico's post.
.. good luck.