How to Install Shutoff Valves

Install stop valves on any faucet

1-2 hours
Install Shutoff Valves

Shutoff valves, also called stop valves, are fitted in several different ways: by soldering, threading or compression. They also come in a variety of combinations that give you options for connecting supply lines and controlling the water supply near your fixtures. This guide will walk you through the process of installing shutoff valves.

What You Need

Cut the supply line
Cut supply line - Install Shutoff Valves

Turn off the main water supply valve and open the faucet to drain the line.
Cut the supply line, leaving enough room between the escutcheon plate and the cut to allow installation of the fitting.

Tip: When cutting the supply line, cut slowly and gently so as to keep the line round. If it’s bent, the copper won’t accept the compression fitting and will leak.

Add compression nut
Add compression nut - Install Shutoff Valves

• Slide the compression nut over the supply pipe.
• Deburr the pipe with emery cloth.
• Slide the nut as far back on the pipe as possible to give yourself room to work.

Insert compression ring
Insert compression ring - Install Shutoff Valves

• Place the compression ring over the end of the supply pipe.
• The ring, also called a ferrule, should completely cover the end of the supply pipe.

Thread compression valve
Thread compression valve - Install Shutoff Valves

• Thread the compression valve into the compression nut.
• The valve should slide squarely and snugly over the ring.
• Thread the compression valve onto the nut and hand-tighten.
• If the nut doesn't turn easily, add a tiny drop of oil to the threads.

Tip: Don't use pipe compound; the fittings don't require it and can actually make the fitting leak.

Tighten the compression valve
Tighten compression valve - Install Shutoff Valves

• Tighten (but don't over-tighten) the compression valve to the nut.
• Finish tightening the nut using one wrench to hold back the valve while keeping it square and another one to turn the nut.
• Connect the other side in the same manner.

Attach supply lines
Attach supply lines - Install Shutoff Valves

• Attach the supply lines to the valve.
• If you are reattaching the old lines to the new valve, follow the same procedure you used to install the valve.
• If you are replacing the old supplies with new braided flexible lines, you will have to remove the old supplies from the faucets before you proceed.

Check for leaks
Check for leaks - Install Shutoff Valves

• Turn on the main water supply and open the supply valves.
• Let the water flow through the faucet to clear air in the lines and test the fittings for leaks by feeling the fittings and examining them with a flashlight.
• Tighten as necessary until the joints are sealed.