How to Fix a Leaky Faucet: Diagnosis, Repair, and Safety

The right repair depends on the faucet design and the exact location of the leak. Compression, cartridge, ball, and ceramic-disc faucets use different internal parts. Before buying a repair kit, identify the manufacturer and model when possible and observe whether water leaks from the spout, handle, base, or supply connection.

Locate the source of the leak

A spout drip often points to worn internal seals or a damaged cartridge. Moisture around the handle may involve packing, O-rings, or a loose retaining component. Water below the sink may come from supply connections, shutoff valves, the drain assembly, or splash rather than the faucet body.

Dry the area, operate the faucet, and observe where moisture first appears. Do not assume the visible drip is the origin; water can travel along tubing and cabinetry.

Prepare before disassembly

Close both fixture shutoff valves and verify that water flow stops. Protect the drain so screws and small parts are not lost. Photograph the handle and component order as pieces are removed, and use tools that fit without damaging decorative finishes.

If a shutoff valve begins leaking when operated, do not force it. Older valves and corroded piping may fail during routine work and require professional replacement.

Match the replacement components

Cartridges, stems, seats, springs, washers, and O-rings vary by manufacturer. A part that looks similar may not seal correctly. Bring the original component or model information to a plumbing supplier and use materials approved for potable water.

Clean mineral deposits gently and inspect mating surfaces. A damaged valve body, cracked fixture, or severely corroded connection may make full faucet replacement more practical than repeated small repairs.

Reassemble and test slowly

Reinstall components in the original orientation and tighten them securely without excessive force. Over-tightening can crack plastic parts, distort seals, strip threads, or damage supply connections.

Open the shutoff valves gradually while watching every disturbed connection. Test hot and cold operation, the handle range, the spout, the base, and the cabinet below. Recheck after several minutes.

Consider pressure and recurring leaks

A new seal may fail quickly when water pressure is excessive or debris repeatedly damages internal parts. Hammering pipes, frequent appliance-valve failures, or leaks at several fixtures can justify a broader plumbing evaluation.

A plumber can measure pressure, evaluate the pressure-reducing valve and thermal expansion, and determine whether water quality or system conditions are contributing to repeated problems.

Know when replacement is the better choice

Replacement may be appropriate when the body is cracked, finishes are badly deteriorated, parts are obsolete, mounting hardware is unstable, or repairs have not stopped the leak. New fixtures still require compatible supply connections and proper sealing.

Hidden deterioration beneath the sink should be corrected before mounting a new faucet. Swollen cabinetry, soft materials, or microbial growth may require drying and repair beyond the fixture itself.

Warning signs that deserve prompt attention

• Water collecting inside the cabinet
• A shutoff valve that will not close or begins leaking
• Corroded, kinked, or damaged supply lines
• Repeated leaks after correct part replacement
• Soft, stained, or swollen surrounding materials

What a home inspection can document

During a home inspection, visible fixtures are operated when conditions permit. The inspector may document active leakage, loose fixtures, damaged supply connections, drainage concerns, staining, or cabinet deterioration.

A visual inspection cannot predict every failure or replace evaluation by the appropriately licensed contractor. It can identify visible concerns, explain why they matter, and help buyers and homeowners plan qualified follow-up.