Replace Water Shut Off Valve Under Bathroom Sink

The water shut-off valve under your bathroom sink is an essential component of your plumbing system. It allows you to turn off the water supply to your sink quickly in case of a leak or other emergency. Over time, these valves can become worn or damaged, and they may need to be replaced.

Replacing a water shut-off valve is a relatively simple task that can be completed in a few hours. By following these step-by-step instructions, you can save yourself the cost of hiring a plumber.

Tools You Will Need

Adjustable wrench
Flathead screwdriver
Phillips head screwdriver
New water shut-off valve
Teflon tape

Step-by-Step Instructions

Turn off the water supply to your sink. The main water shut-off valve for your home is usually located in the basement or utility room. Turn the valve clockwise to close it.
Open the faucet on your sink. This will relieve any pressure in the water lines.
Locate the water shut-off valve under your sink. It is usually located behind the sink, near the base of the faucet.
Place a bucket or bowl under the valve to catch any water that may leak out.
Use an adjustable wrench to loosen the packing nut on the valve. The packing nut is the large nut that connects the valve to the water line.
Remove the old valve from the water line.
Apply a few wraps of Teflon tape to the threads of the new valve. This will help to create a watertight seal.
Screw the new valve onto the water line.
Tighten the packing nut on the valve. Be sure to tighten it snugly, but do not overtighten it.
Turn on the water supply to your sink.
Check for leaks. If you see any leaks, tighten the packing nut further.

Tips

If you are not comfortable replacing the water shut-off valve yourself, you can call a plumber to do it for you.
It is a good idea to replace the water shut-off valve every 5 to 10 years, even if it is not leaking. This will help to prevent future leaks.
If you have a leak in your water shut-off valve, it is important to replace it as soon as possible. A leak can cause water damage to your home.