A leaky, dripping faucet can be annoying enough to keep you awake at night. And it's not just that: A dripping faucet can waste an incredible amount of water. One drip each second can waste up to 3,000 gallons per year. That's enough to fill close to 40 bathtubs.
Leaks can stain sink surfaces, corrode drains, tax plumbing lines, waste energy (when the leak is hot water), and generally do nothing good for you or your home.
Why Your Faucet Leaks or Drips
Faucets either have sink cartridges or compression valves that open and close to control the flow of water. Most faucet leaks are the result of worn cartridges or worn stem assembly washers. Replacing these parts cures most faucet leaks.
Worn Sink Cartridge
Single- and double-faucet handle faucets often contain sink cartridges hidden under the faucet handles that control the flow of water. Made of plastic and metal, sink cartridges are self-contained and cannot be repaired—but they can be removed and replaced on a one-for-one basis.
Since sink cartridges are specific to the brand and model of faucet, you'll need to purchase the exact type of cartridge for your bathroom or kitchen faucet.
Worn Compression Faucet Washer
Another style of faucet is the compression valve faucet. Common with older homes, compression faucets shut off the water when the faucet handle is turned, thus compressing a stem washer located within the assembly.
This soft rubber or silicone washer will slowly wear down. No matter how hard you tighten the faucet, the water never quite shuts off all the way.
Replacing the stem washer is usually the cure for this type of leak. This is a simple, inexpensive fix that takes care of most compression faucet leaks.
Compression valve stem washers are usually sold in inexpensive kits that have an assortment of 10 to 15 washers and screws of various sizes. This allows you to use the washer and screw that fits your faucet.
How to Shut off Water to the Faucet
Turn off the water to the faucet at its closest point: directly below the sink. Open the cabinet door to locate the two braided water supply lines and two shut-off valves. Shut off each line individually by turning the knob or lever clockwise until it is tight.
If the water does not shut off completely, turn off the main water shut-off valve to the entire house. This valve is often located on the inside perimeter of the home on the side facing the street.
How to Repair a Two-Handle Cartridge Faucet
Equipment / Tools
- Adjustable wrench
- Channel-lock pliers
- Set of Allen keys
- Flathead screwdriver
- Phillips-head screwdriver
- Utility knife
- Replacement faucet cartridge (if needed)
- Silicone faucet grease
- Kit of assorted stem washers and screws
How to Fix a Leaky Cartridge Faucet
Remove Screw From Handle
After shutting off the water and plugging the sink drain, remove the faucet handle. Often, there is an Allen (or hex) screw located on the side or back of the handle. Insert the end of the Allen key into the screw and turn counter-clockwise. Remove the screw and set it safely aside.
Remove Faucet Handle
Lift the handle straight up to remove it.
Loosen Retaining Nut
A thin retaining nut holds the sink cartridge in place. Clamp the adjustable pliers around the retaining nut. Turn counter-clockwise to loosen the nut. Turn out the nut the rest of the way by hand.
Remove Sink Cartridge
Grab the top of the sink cartridge and pull it up to remove it. You may need to gently wiggle the cartridge to first loosen it before removing it.
Apply Silicone Grease
With your finger, apply a small amount of silicone faucet grease to the body of the replacement faucet cartridge.
Insert Replacement Cartridge
Align the tabs of the replacement cartridge with the slots on the faucet. Slide the cartridge straight down until it fully seats. With the wrench, apply the retaining nut.
Install the Handle
Install the faucet handle again with the Allen key and the Allen screw.
Test Water Flow
Turn on the water supply valves. Let the faucet run for about a minute, then turn it off again. Check for leaks.
How to Fix a Compression Faucet
After shutting off the water and stopping up the drain, remove the faucet handle either with the Allen key or with a Phillips-head screwdriver. Some faucets may have a decorative cap over the screw. Remove this cap with a flat-head screwdriver or the edge of a utility knife. Unscrew the handle and set it and its screw aside.
Remove Valve Cover
The valve stem assembly may have a cover over it, which you remove by unscrewing the knob with pliers.
Remove Valve Stem Assembly
With pliers, grip the hex head of the valve stem assembly. Screw counter-clockwise to remove it.
Note that the hex screw head is integrated into the valve stem assembly. It is not a separate retaining nut.
Remove Washer Screw
Use the Phillips-head screwdriver to remove the screw holding the stem washer in place.
Remove Stem Washer
With your fingernail or the edge of the utility knife, pick the stem washer out of the valve stem assembly.
Replace Stem Washer
Firmly place the new stem washer on the valve stem assembly. Screw the washer screw over the top.
Replace the valve cover (if applicable). Attach the handle. Add any decorative caps over the top.
Turn on the water again below the sink and let it run for about a minute. Turn off the faucet and check for leaks.
When to Replace Your Leaky Faucet Instead of Fixing It
Faucet Is 10 to 20 Years Old
Faucets that are more than 10 to 20 years old may have other issues. Much like an old car, the faucet will work for a while until yet another section of it breaks down. Eventually, it's easier and less expensive to buy a new one.
Repairs Take Too Long
Leaky faucet repairs should take a half-hour or up to an hour. You shouldn't be spending hours working on your bathroom or kitchen faucet. If it's over an hour and you're still working on your faucet, you may want to consider replacing it instead.
Repairs Cost Too Much
Balance the cost of the repairs against the cost of replacement. An inexpensive faucet may not be worth repairing unless you only need to replace a few washers. Expensive faucets usually are worth repairing.
The cost of the faucet cartridge is usually the determining factor, since this is the most expensive part. Most faucet cartridges cost from $10 to $50, with a few cartridges in the $50 to $100 range.
Repairs Aren't Working
Faucets are mechanical devices that see constant use, so they don't last forever. If you cannot repair the dripping faucet on your own, it's usually time to pull it out and replace it with a new faucet.
When to Call a Professional
Plumbers can repair most leaky faucets, plus they can replace faucets if necessary. While bathroom and kitchen faucets can generally be repaired or replaced by most homeowners, plumbers can step in and do the job instead if it is cumbersome or complicated.
Plumbers—especially emergency plumbers—can be expensive, even for the short amount of time needed to repair a faucet. Before making a call, weigh the cost of the plumber against the cost of purchasing a new faucet.
"Fix a Leak Week." United States Environmental Protection Agency.