A leaky faucet has a torturous way of wearing on nerves and water resources. Even a slow drip can waste hundreds of gallons or liters per month. Luckily, most dripping washer-type faucets can be cured in 30 minutes for less than a dollar.
To repair a washer-type faucet, you'll need to replace the washer on the bottom of the valve stem and some times replace the valve seat as well. Replace washers for both the hot and cold water while you're at it, not just the one that's leaking. Before you begin, turn off the water-supply valves and close the sink stopper so small parts won't disappear down the drain.
Most faucet handles are secured by a screw, which is sometimes covered by a snap-on cap or button. You may need to tap, wiggle or pry the handle a bit to remove it. The washer on the end of the valve stem may be flat or beveled. The new washer should be the same profile and fit snugly inside the circular lip without having to be forced.
With your finger, feel down inside the area where the stem assembly enters the faucet to determine whether the valve seat is rough or grooved. If it's , replace it with a new valve seat that exactly matches the old in diameter, height and threads.
1. Remove screw holding handle, then loosen and remove packing nut. Remove stem assembly.
2. Remove worn washer and replace it with correct type: flat or beveled. New washer should fit snugly without being forced.
3. Use seat wrench to remove worn valve seat. New seat must match old one exactly in diameter height and number of threads.
4. Lubricate working parts of stem assembly with heat- proof faucet grease. Reassemble faucet.
Repairing an Outdoor Faucet
Most outdoor faucets, including the freeze-proof one shown, have a washer at the end of the valve stem. Freeze-proof faucets are particularly prone to worn washers because, when the faucet is turned off, it continues to drain for a few seconds; consequently, people tend to turn the faucet tighter, damaging the rubber washer. Before beginning your repair, turn off the faucet's water supply.
1. Unscrew handle and remove packing nut. Hold faucet steady while loosening the nut to avoid twisting the interior pipe. Even hard copper pipe can be twisted.
2. Pull stem out of faucet. For removal, some stems have to be turned so a key lines up with a slot; reattach handle to turn and pull stem.
3. Remove and replace rubber washer on the stem end. If there are rubber O-rings on stem, replace these as well.
Installing a Frost-proof Faucet
Frost-proof faucets work by shutting off water flow inside a heated space, away from freezing temperatures. New frost-proof faucets frequently have a built-in anti-siphon device to prevent cross-connections. Install the faucet at a slight downward pitch to allow the stem housing to drain.
Recommended Reading
| 
If you need supplies, tools or equipment for your DIY project, we recommend these trusted online merchants...
...they will deliver even the big stuff right to your door -- all at very reasonable prices.
Want to learn more about plumbing? Visit our plumbing library.
Plumbing: 23,000-item online catalog!
Got a wet basement? Visit our site dedicated to Basement Waterproofing.
