A leaking kitchen faucet can be fixed by identifying the type of faucet, turning off the water supply, and replacing the worn-out seals or cartridges. This guide explains how to repair a leaking kitchen faucet step by step, using common tools and parts available at any hardware store.
Understanding Your Kitchen Faucet Type
Before you start, determine which of the four common faucet types you have. Each has a different internal mechanism, so the repair approach varies. Knowing your faucet type also helps when purchasing replacement parts.
Compression Faucets
These traditional faucets have separate hot and cold handles. A leak usually comes from a worn rubber washer on the valve seat or a deteriorated O-ring under the handle. They are the easiest to repair but less common in modern kitchens. You can identify them by the two distinct knobs that require multiple turns to open/close.
Cartridge Faucets
Cartridge faucets use a cylindrical cartridge to control flow and temperature. Leaks often require replacing the entire cartridge. They are found in many single-handle designs and sometimes in two-handle models. To identify, look under the handle – if you see a metal or plastic cylinder, it's a cartridge type.
Ball-Type Faucets
Common in older single-handle kitchen faucets, ball faucets use a rotating ball with slots to mix hot and cold water. Leaks can stem from worn seat springs, rubber seals, or a damaged ball. The handle typically moves in a smooth arc with limited rotation. A hex screw often holds the handle in place.
Disc Faucets
Disc faucets feature a ceramic disc cartridge that is very durable and resistant to wear. Leaks are rare but may occur if debris scratches the disc or if the inlet seals fail. Replacement is straightforward – the entire disc cartridge is swapped out. You can identify disc faucets by the wide, low-profile handle and the two ceramic discs visible once the cartridge is removed.
Tools and Materials Needed
Gather these items before starting to avoid trips to the store:
- Adjustable wrench (or set of wrenches)
- Allen wrench set (hex keys) – typically 3/32″, 1/8″ or 9/64″
- Screwdrivers (flat-head and Phillips)
- Plumber's tape (Teflon tape) for threads
- Replacement parts: cartridge, O-rings, washers, valve seat or disc assembly (exact part depends on your faucet model)
- Bucket and towels to catch water
- Penetrating oil (e.g., WD-40) if parts are stuck
- Flashlight and plumber's grease for lubricating O-rings
Step-by-Step Repair Guide
1. Turn Off the Water Supply
Locate the shut-off valves under the sink – usually two (hot and cold). Turn them clockwise until fully closed. If no shut-off valves are present, shut off the main water valve for the house (often near the water meter). After closing the valves, open the faucet handle to relieve pressure and drain any remaining water. Place a bucket under the faucet to catch drips.
2. Disassemble the Faucet
Remove the decorative cap on the handle (if present) using a flat-head screwdriver. Underneath you'll find a screw – usually an Allen screw or Phillips screw. Unscrew it and lift the handle off. For compression faucets, you'll then need to unscrew the packing nut with a wrench to access the stem. For cartridge faucets, a retaining nut holds the cartridge in place – unscrew it carefully. For ball faucets, remove the handle and then use pliers to pull the ball assembly. For disc faucets, lift the handle and unscrew the cartridge retaining screw. Keep all parts organized.
3. Replace Worn Parts
Inspect every seal, O-ring, washer, and cartridge for cracks, flattening, or mineral buildup. Replace any damaged components with matching parts from your kit. Apply plumber's tape to any threaded connections (wrap clockwise 2-3 times). Apply a thin layer of plumber's grease to new O-rings to help them seat properly. For compression faucets, also inspect the valve seat – if it's rough or pitted, use a seat wrench to replace it. Always follow the manufacturer's diagrams if available.
4. Reassemble and Test
Reassemble in reverse order. Tighten all nuts and screws firmly, but avoid overtightening – this can crack parts or strip threads. Turn the water supply back on slowly, check for leaks immediately, then open the faucet fully to flush any debris. If the leak persists, double-check that O-rings are seated correctly or consider replacing additional seals.
Common Leak Causes by Faucet Type
| Faucet Type | Common Failure Point | Solution |
|---|---|---|
| Compression | Worn rubber washer on valve seat | Replace washer and seat if pitted |
| Cartridge | Damaged O-rings or cartridge | Replace cartridge and O-rings |
| Ball | Worn seat springs or seals | Replace springs, seals, or ball |
| Disc | Scratched ceramic disc or loose inlet seals | Replace disc cartridge or seals |
Troubleshooting Common Issues
- Faucet still leaks after part replacement: Double-check that all parts are correctly seated – a misaligned O-ring is a frequent cause. Also inspect the valve seat for pits. If the seat is damaged, a seat wrench can replace it.
- Low water pressure after repair: Debris may have lodged in the aerator. Remove the aerator (unscrew from the spout) and clean the screen with a brush. Rinse thoroughly and reinstall.
- Water leaking from the handle base: This usually indicates a worn O-ring on the cartridge or stem. Turn off water, disassemble, replace the O-ring, and lubricate with plumber's grease.
- Handle hard to turn: Mineral buildup or overtightened packing nut. Apply penetrating oil to loosen buildup, or loosen the packing nut a quarter turn. Avoid forcing the handle.
- Leak at the base of the spout: Often due to a worn spout O-ring or seal. You may need to pull the spout straight up and replace the underlying seals.
Repair vs. Replacement – Making the Call
If your faucet is more than 10-15 years old or the body is corroded, replacing the entire faucet may be more cost-effective than multiple repairs. Modern faucets often come with lifetime cartridges and are designed for easier service. However, if the leak is minor and the faucet is in good condition, a simple part replacement is the most economical route. Typical professional repair costs in the U.S. range from $100 to $350 depending on faucet type and local labor rates – a new faucet installation starts around $150 and can exceed $500 for premium models.
When to Call a Professional
While many kitchen faucet leaks can be repaired DIY, some situations warrant a licensed plumber. If you encounter stripped threads, corroded pipes under the sink, a leak that persists after multiple attempts, or if you're uncomfortable with disassembly, it's best to call an expert. At MyTownPlumber, we offer comprehensive leak detection for hidden leaks in walls or floors, pipe repair for underlying supply line issues, and toilet repair for related bathroom plumbing problems. Our technicians are trained to diagnose and fix all major faucet brands quickly.
Preventing Future Leaks
Regular maintenance extends the life of your kitchen faucet. Clean the aerator annually to remove sediment. Avoid using excessive force when turning handles – a gentle touch reduces wear on O-rings and cartridges. Address drips promptly because even a slow drip can waste over 3,000 gallons per year according to EPA WaterSense. Choosing WaterSense-labeled fixtures when replacing a faucet reduces water use without sacrificing performance. Always follow local plumbing codes – the International Association of Plumbing and Mechanical Officials (IAPMO) provides standards that help ensure safe, efficient installations.
If you'd rather leave the repair to the pros, MyTownPlumber offers expert faucet repair services with a satisfaction guarantee. Click here for a special offer on plumbing services.
By MyTownPlumber Editorial Team