How far to turn stopcock is a vital bit of knowledge every home owner should know. The reason being, should a leak develop it is important to be able to shut the water off as soon as possible before the damage gets out of hand. It is also a good idea to have a understanding of how your internal and external stop taps work so that you can help your plumber find the problem quickly.
Your internal stop tap (also called a ‘stop valve’) is what turns off the water to your whole property. This is usually in the kitchen under a sink but could be in a utility room or under floorboards in older properties. In fact, it could be anywhere in your home depending on the age and design of your house.
From Pipes to Fixtures: Exploring the Components of Your Home Plumbing System
The external mains stopcock is another important bit of plumbing you should be familiar with and it’s what stops the water supply to your property from the street. This is what needs to be turned off when a burst pipe is discovered and until the emergency plumber arrives. Emergency plumbers will have a special stopcock key that can be used to shut off water supplies at street level so they can repair any problems and then safely turn the water back on when they’re happy it’s safe.
A lot of people have trouble turning their stopcock because it is stiff from being in one position for a long time. However, WD40 can often be used to lubricate the handle and if you use it with care (not forcing hard) it should loosen up. This is because a stopcock can become stiff when scale or dirt builds up on the threads.