How to Install Shut Off Water Valves

shut off water valve
  • 1-10 hours
  • Beginner
  • 25-250
What You'll Need
Supply lines
Pipe cutter
Teflon tape
Plumbing joint compound
What You'll Need
Supply lines
Pipe cutter
Teflon tape
Plumbing joint compound

Most houses built in the last few years have shut off valves installed on the hot and cold supply lines running to taps in kitchens and bathrooms. A shut off valve allows you to turn off the water supply to an individual tap, but still leave the water on in the rest of the house. If you've ever had to turn off the water in the whole house just to replace an appliance, you understand how individual valves can make everybody's life easier.

If you live in an older house or your builder didn't put shut off valves into your pipes, you might want to consider adding them yourself. The installation process is straightforward, as most use pressure couplings so that you don't need to worry about soldering any pipes, and it's the kind of installation homeowners can do themselves with standard plumbing tools.

Here's how you can install shut off valves on your existing copper supply lines.

Step 1

First check to see how your supply lines connect to your sink. Some lines come right up through the floor to the base of the faucet, while others come out of the wall behind the sink and bend upward at a 90 degree angle to get to the faucet base.

When the plumbing comes up through the floor, you will install straight valves. If your water pipes come from behind the wall, you have an option. If the vertical run of the supply line is 8" to 10", you could install a straight shut off valve in the run. If it's not that long, you can install an angled shutoff valve, sometimes called an angle stop. You attach an angle shut off to the horizontal pipe and then run the supply line vertically.

Step 2

Determine where you are going to install the shutoffs, and measure the distance to the base of the faucet. You will need to know this distance in order to buy the right sized supply lines.

Step 3

Steps 1 and 2 will determine what size materials you buy, but once you are done, you can get to work by shutting off the main water supply to the house. This is likely located close to your water meter where the main water supply enters your house. After shutting the water off, open a faucet on the lower level of your home and let the water lines run until it is completely drained.

Step 4

Disconnect the water supply line running to the base of the fixture you will be working on. On some, this will just be a screwed-on connection, and on others, it may be a soldered pipe.

If it's soldered, use a hacksaw or pipe cutter to cut the pipe in two places, about 2" down from the base of the fixture and also 6-10" farther down the pipe. Use the reamer on the pipe cutter to remove any burrs on the copper pipes, and then clean them with a piece of sandpaper or emery cloth until they shine.

Step 5

Slide the compression nut from the shut off valve onto the pipe with the threads facing the open end. Then slide on the compression ring.

Step 6

Wrap the pipe with Teflon® tape or spread plumbing joint compound on the end of the pipe, and then push the shutoff onto the end of the pipe. Slide the compression nut and ring up to the shut off valve and hand tighten the nut.

Step 7

Attach the compression fitting of the flexible supply tube to the other side of the shut off valve and hand tighten it as well. Attach the compression fitting on the supply tube to the base of the faucet and hand tighten it.

Step 8

Once all your compression fittings are attached and hand tightened, use an adjustable wrench to tighten them all firmly. Be careful you don't over tighten as this can bend the soft copper pipe out of round or damage a compression fitting.

Step 9

Turn the water back on and check for leaks. Don't forget to open the shut off valve when you turn on the faucet.

Installing shut off valves is an easy, inexpensive upgrade to your home's plumbing. You don't have to do them all at once, but the next time you have to do any work on your plumbing - even just changing a washer - is a fine time to make the addition. You and your family will all appreciate the added convenience that shut off valves provide.