Why the stopcock matters
Every guide to dealing with a burst pipe starts with the same instruction: turn off the stopcock. That only works if the valve turns. Stopcocks that sit untouched for years often seize in position, and the first time anyone discovers it is during an emergency, with water coming through the ceiling.
It is worth finding yours and checking it turns before you ever need it. If it will not budge, or it weeps from the spindle when you try, that is the moment to have it sorted — calmly, as a planned job rather than a panicked one.
Seized, dripping or broken
A stiff stopcock can sometimes be freed with patience and the right approach, but forcing one risks snapping the spindle or cracking the body, which turns a small job into an urgent one. If a valve resists gentle persuasion, replacement is usually the sensible answer.
A stopcock that drips from the gland around the spindle can occasionally be cured by tightening the gland nut slightly, but on an old valve this is often a temporary reprieve. A new valve ends the uncertainty.
What replacement involves
Replacing the internal stopcock means turning the water off further back — usually at the external stop tap near the property boundary — then draining down, removing the old valve and fitting a new one. We fit modern full-bore lever valves, which turn a quarter turn with two fingers and are far less prone to seizing than the old brass wheel-head type.
If the external stop tap will not turn either, that part belongs to your water supplier, and they will normally attend to it. We can advise on who needs to do what and in which order.
Find yours before you need it
Most internal stopcocks live under the kitchen sink, but in older Harpenden homes they can be in a utility room, under the stairs or where the mains pipe enters the house. Once you have found yours, turn it off and on once or twice a year to keep it free — and make sure everyone in the house knows where it is.
Our burst pipe guide explains the emergency steps that depend on a working stopcock, and the low water pressure guide covers what a partly closed one does to your flow.
Areas we cover
We replace stopcocks and stop taps across Harpenden, St Albans, Wheathampstead, Redbourn, Luton and Hemel Hempstead. See the full list on our areas we cover page.