A must for every home owner is to know where the “internal” stopcock is and make sure it works! Whether you are in a Flat or a House the Internal stopcock would be your immediate place to go if you have a mains cold water leak.
If you cannot find an Internal stopcock, then you need to know where your “Pavement” stopcock is located and whether it works. Most new water meters have an easy to turn valve easily visible, but older pavement stopcocks mostly are just a “square nut” down a hole that may well be covered in mud/dirt and require a “Stopcock Key”
Common Leak Types and Remedies:
Cold water leak and have an Immersion tank (normally in an airing cupboard) then you will have a Tank in the loft which despite turning off a Stopcock will continue to leak until the tank is empty.
Hot water leak and have an immersion tank, then there should be a “Gate vale” – normally a Red Wheel type within the airing cupboard on a cold pipe which goes into the BOTTOM of the tank which can be turned off (No cold water going in means No hot water coming out)
Cold or hot water leak and you have a Combination Boiler (one that turns on only when you want hot water or heating) then you need to turn the main stopcock off and also TURN off the boiler or the power to it! If it is Hot water it may possibly be the heating side and stop the boiler from working before you notice signs of a leak.