A leaky shower faucet usually results from worn internal components, such as cartridges, washers, or seals. Repairing it promptly prevents water waste, wall damage, and mold growth. The exact fix depends on the faucet type and how it controls temperature and flow.

This guide walks through a safe, standard repair process suitable for most residential and commercial showers.

Common Causes of a Leaky Shower Faucet

• Worn or damaged cartridge

• Deteriorated rubber washers or O-rings

• Mineral buildup from hard water

• Loose retaining nut or valve stem

• Corrosion inside the valve body

Tools You May Need

• Adjustable wrench

• Screwdrivers

• Allen key

• Cartridge puller

• Replacement cartridge or washer kit

• Plumber’s grease

• Teflon tape

• Towels and a small bucket

Step 1: Shut Off the Water Supply

• Turn off the main water supply or the shower’s isolation valves

• Open the shower faucet to release remaining pressure

• Confirm the water is fully off before proceeding

Step 2: Remove the Shower Handle

• Locate the set screw, often hidden under a decorative cap

• Remove the screw using a screwdriver or Allen key

• Pull the handle straight off the valve stem

If the handle is stuck, gently wiggle it instead of prying.

Step 3: Remove the Trim Plate

• Unscrew the trim plate or escutcheon

• Cut away silicone sealant if present

• Pull the plate away to expose the valve assembly

This step provides full access to the leaking components.

Step 4: Identify the Faucet Type

Determine which internal part needs repair:

• Cartridge faucet – Common in modern single-handle showers

• Compression faucet – Uses washers and valve stems

• Pressure-balance or thermostatic valve – Often requires cartridge replacement

Correct identification ensures the right replacement parts are used.

Step 5: Remove and Inspect the Internal Component

For Cartridge-Type Faucets

• Remove the retaining clip or nut

• Pull the cartridge straight out using pliers or a cartridge puller

• Inspect for cracks, wear, or mineral buildup

For Compression Faucets

• Unscrew the valve stem

• Remove and inspect the washer and O-ring

• Replace any hardened or cracked parts

Step 6: Clean the Valve Body

• Remove debris and mineral deposits inside the valve housing

• Wipe surfaces clean before installing new parts

• Apply plumber’s grease lightly to O-rings

Clean surfaces help ensure a proper seal.

Step 7: Install Replacement Parts

• Insert the new cartridge or washer assembly correctly aligned

• Reinstall retaining clips or nuts securely

• Avoid overtightening, which can damage seals

Step 8: Reassemble the Faucet

• Reinstall the trim plate and handle

• Apply new sealant if required

• Tighten fasteners evenly

Step 9: Restore Water and Test

• Turn the water supply back on slowly

• Test for leaks with both hot and cold water

• Ensure smooth handle operation and stable temperature control

Common Problems and Solutions

When to Replace Instead of Repair

• Valve body is heavily corroded

• Persistent leaks after cartridge replacement

• Cracked valve housing

• Incompatible or discontinued parts

In these cases, replacing the entire shower valve may be more reliable.

Summary

Repairing a leaky shower faucet typically involves replacing worn internal components rather than the entire fixture. With the water supply shut off and the correct replacement parts, most leaks can be fixed efficiently and safely.