A drip is easy to ignore, but it adds up. The EPA’s WaterSense program says a faucet dripping once a second can waste more than 3,000 gallons a year. The City of Calgary puts the same drip at about 2.5 cubic metres a month. The fix is usually one small, inexpensive part. The trick is knowing which one.
The four kinds of faucet
The City of Calgary’s repair guide sorts household faucets into a washer type and three washerless types. You can usually tell them apart before you pick up a tool.
| Type | How to recognize it | What usually wears out |
|---|---|---|
| Compression (washer) | Separate hot and cold handles that you turn until they tighten. Often older. | The rubber stem washer and O-ring, and sometimes the valve seat. |
| Cartridge | One lever or two handles. Inside, a narrow metal or plastic cartridge slides into the body. | The cartridge’s O-rings, or the whole cartridge. |
| Ball | A single lever over a rounded cap. The lever moves a hollow ball inside. | O-rings, the cam washer, and the seats and springs under the ball. |
| Ceramic disc | A single lever over a wide, round body. Inside is a cartridge with ceramic discs. | The inlet seals. If those don’t stop it, the cartridge. |
Tub and shower valves work the same way, but most of the valve sits behind the wall. See Replace a shower cartridge.
Find the brand and the exact part
Two faucets that look alike can take different parts. Moen’s own cartridge guide warns that some cartridges look similar but aren’t interchangeable, and neither are their retainer nuts. It identifies cartridges by how far the handle turns, where the handle screw hides (under a cap, behind a plug button or in a small hole) and roughly when the faucet was installed.
- Look for a brand logo on the handle, the spout or the escutcheon plate.
- Check under the sink for a model tag on the supply lines, or find the paperwork.
- Take the old part to the store if you can’t identify it. Lay every piece out in the order it came off, and photograph each step.
Before you start
- Shut off the water at the two valves under the sink, then open the faucet to drain it. Tubs and showers usually have no shut-off valves, so use the main. See how to shut off your water, power and gas.
- Plug the drain or lay a towel in the sink so small screws can’t fall in.
- Tape your screwdriver tip or wrap the wrench jaws in cloth so you don’t scratch the finish.
- Don’t force a stuck handle. Calgary’s guide suggests a handle puller instead.
The fix for each type
- Compression: take off the handle, unscrew the packing nut and lift out the stem. Replace the washer and O-ring, and clean the seat. Calgary recommends doing both the hot and cold sides, even if only one leaks.
- Cartridge: remove the retainer nut or clip, note which way the cartridge faces, then pull it. Replace the O-rings, or the cartridge if it’s worn.
- Ball: a leak at the base usually means O-rings. A leak at the handle often means tightening the adjusting ring or replacing the cam washer. A spout drip means new seats and springs. Put the ball back in its original position.
- Ceramic disc: replace the inlet seals first. If it still drips, replace the cartridge with a kit for that model.
Turn the water back on slowly, with the faucet open, so trapped air doesn’t spit grit into the new seals.
If the pressure is low, check the aerator first
A weak or sputtering flow often isn’t the valve at all. Unscrew the aerator at the tip of the spout. If it’s crusted with minerals, soak it in vinegar, or replace it. See Low water pressure.
When to replace the faucet instead
If the body is cracked, it leaks from the base, the parts are no longer sold, or you’ve rebuilt it before, a new faucet is often the better job. See Replace a kitchen faucet. Call a plumber if a shut-off valve won’t close, or if the leak is in the wall behind a shower.
Watch it done
Fix a leaky faucet collects videos for each faucet type, and Faucet drips starts from the symptom. More jobs are under Plumbing.