Bathtub Faucet Leaking? Find the Cause and Fix the Drip

A bathtub faucet leaking from the spout or handle usually means a worn cartridge, washer or O-ring, or a failing diverter. Turn off the water, identify your faucet type, replace the worn part, and check for hidden leaks if the wall or the ceiling below is damp. Even a slow drip wastes water and can rot a wall.

Bathtub faucet leaking: where the water comes from

Where it leaks	Likely cause
Drips from the spout when off	Worn cartridge, washer or valve seat
Leaks around the handle	Worn O-ring or loose packing
Water comes from the tub spout when the shower runs	Failing diverter
Drip from the showerhead when off	Cartridge or valve fault
Water on the wall or floor	Leaking supply or joint behind the wall

Quick facts: bathtub faucet leaking
Time	About 30 to 60 minutes for a cartridge swap
You need	Screwdrivers, adjustable pliers, hex key, replacement part, cloth
First step	Shut off the water at the stop valves or the main
Not a DIY job if	The leak is inside the wall or shutoffs fail

Identify your faucet

A single handle that turns to mix hot and cold usually has a cartridge or a ball valve. Two handles often use compression washers or two cartridges. Look for the brand name on the handle or trim, then buy the exact replacement part. Photograph the old part before you remove it.

Fix a cartridge faucet

1. Turn off the water at the stop valves, or the main if there are none.
2. Remove the handle cap, undo the screw and pull the handle off.
3. Remove the trim plate and the retaining clip or nut.
4. Pull out the cartridge with pliers or a puller. Note its orientation.
5. Install the new cartridge the same way, replace the O-rings and reassemble.
6. Turn the water back on slowly and test for drips.

Fix a two-handle compression faucet

Remove each handle, unscrew the stem, replace the rubber washer at the base and the O-ring, check the valve seat for pitting and reassemble. A damaged seat may need a seat wrench or a new valve.

Diverter leaks

If water streams from the spout while the shower runs, the diverter is worn. Some are built into the spout and replaced by swapping it, and others sit behind a trim. Check the spout type and replace it or the diverter parts.

Signs of a hidden leak

Water stains on the ceiling below, soft or discolored drywall around the tub, mold smell or a rising water bill suggest a leak inside the wall. Stop using the tub, shut off the water to it and call a plumber, because drywall and framing can rot quickly. If it is on an upper floor, check the ceiling underneath.

Preventing future leaks

Replace old cartridges and washers before they fail, do not over-tighten handles and clean mineral buildup. Check around the spout caulk to keep water from seeping behind the wall.

Tools and parts checklist

Before you start, gather a flat and a Phillips screwdriver, a hex key set, adjustable pliers, a small bucket, a rag, plumber's grease and the replacement cartridge, washers or O-rings. Take the old part with you to the store if you cannot find the brand. Put a towel in the tub so a dropped screw does not scratch the finish or vanish down the drain, and stuff a rag in the drain opening.

Hot side, cold side or both?

If the drip stops when you close one stop valve, you have found the guilty side. Single-handle faucets mix both sides in one cartridge, so replace the whole cartridge. On two-handle faucets, replace the washer on the side that leaks, and the other washer too if it looks hard or cracked.

When to call a professional

If you cannot find the brand, the leak continues after replacing the part, the shutoffs are stuck or you suspect a leak in the wall, a plumber can solve it without opening more of the wall than necessary. A bathtub faucet leaking is easy to fix when it is the cartridge, and worth urgent help when it is inside the wall.

Related reading

• How to Fix a Leaky Faucet: Find the Type, Replace the Part
• Outdoor Faucet Leaking? Find the Leak, Fix It, Winterize
• How to Increase Water Pressure in Your House: 7 Checks
• Water Stain on Ceiling: Find the Source, Dry It and Repair It

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