How to Fix a Leaky Bathtub Faucet with One Handle [In 2025]

Have you ever been driven crazy by the constant drip-drip-drip of a leaky bathtub faucet? Not only is that sound annoying, but it’s also literally money going down the drain. A leaky faucet can waste hundreds of gallons of water per year, increasing your water bill and harming the environment. The good news? Fixing a single-handle bathtub faucet is often a straightforward DIY project that you can tackle in a single afternoon.

In this comprehensive guide, I’ll walk you through exactly how to silence that irritating drip and save yourself both the headache and the expense of calling a plumber. You don’t need to be a plumbing expert to fix this common household problem—just follow these detailed instructions, and you’ll have your faucet working like new in no time.

Understanding the Basics of a Single-Handle Bathtub Faucet

Before diving into repairs, it’s important to understand what we’re working with. A single-handle bathtub faucet, as the name suggests, uses just one handle to control both hot and cold water flow. These faucets are popular because of their streamlined appearance and ease of use.

Common Types of Single-Handle Faucets

Single-handle faucets typically fall into a few categories:

1. Ball-type faucets: These contain a ball-shaped mechanism that controls water flow and temperature. Less common in bathtubs but worth mentioning.
2. Cartridge faucets: The most common type for bathtubs, these contain a cylindrical cartridge that moves up and down to control water flow and rotates to adjust temperature.
3. Ceramic disk faucets: These use ceramic disks that slide against each other to control the water flow. They’re known for durability but are less common in older tub installations.

In most cases, your single-handle bathtub faucet is likely a cartridge type, and the repair procedure we’ll discuss focuses primarily on this variety.

Identifying the Source of the Leak

Before you start disassembling your faucet, take a moment to identify where exactly the leak is coming from:

• If water is dripping from the spout when the faucet is turned off, the issue is likely with the cartridge or seals inside the faucet.
• If water is leaking around the handle itself, the problem might be with the O-rings or the packing.
• If water is leaking from the base of the spout, you might have an issue with the spout connection.

For most single-handle bathtub faucets, a drip from the spout indicates a worn cartridge that needs replacement—which is what we’ll focus on in this guide.

Tools and Materials You’ll Need

Getting prepared with the right tools and materials before you start will make this repair job much smoother.

Essential Tools for the Job

• Phillips and flathead screwdrivers
• Adjustable wrench
• Allen wrench set (hex keys)
• Needle-nose pliers
• Utility knife
• Penetrating oil (like WD-40)
• Clean rags or towels

Optional Tools That Make the Job Easier

• Faucet handle puller (if your handle is stuck)
• Socket wrench set
• Flashlight or headlamp (for better visibility)
• Small mirror (to see hidden parts)
• Digital camera or smartphone (to take reference photos)

Materials You Might Need to Replace

• Replacement cartridge (specific to your faucet model)
• O-rings and washers
• Plumber’s grease (silicone-based)
• Vinegar (for cleaning mineral deposits)
• Plumber’s tape (Teflon tape)

Remember that the specific cartridge you need depends entirely on your faucet’s brand and model. If possible, take the old cartridge to your local hardware store to ensure you get an exact match, or look for the manufacturer information on the faucet itself.

Preparing for the Repair

Proper preparation can save you headaches and wet floors.

Shutting Off the Water Supply

This is the crucial first step. You have a few options:

1. Use the dedicated shut-off valves for your bathtub if they’re accessible (often behind an access panel).
2. Shut off the main water supply to your house if individual shut-off valves aren’t available.
3. Turn off the water at the water meter as a last resort.

After shutting off the water, turn on the faucet to drain any remaining water from the lines and relieve pressure.

Protecting Your Bathtub and Work Area

• Cover the drain with a washcloth or drain cover to prevent small parts from falling in.
• Place towels in the tub to catch water and protect the surface from dropped tools.
• Set up a clean workspace nearby to organize parts as you remove them.
• Consider taking photos at each step of disassembly to help with reassembly later.

Step-by-Step Guide to Fixing Your Leaky Faucet

Now that you’re prepared, let’s dive into the actual repair process.

Removing the Handle

1. Look for a small decorative cap on the handle, usually marked hot/cold or with a color indicator.
2. Pry this cap off gently with a flathead screwdriver.
3. Underneath, you’ll find a screw that secures the handle to the stem. Remove this screw with the appropriate screwdriver (usually Phillips).
4. Pull the handle straight off. It should slide right off the stem, but it might require some gentle wiggling.

Dealing with Stuck or Corroded Handles

If your handle is stubborn and won’t budge:

1. Apply penetrating oil around the base of the handle and let it sit for 15-20 minutes.
2. Try wiggling the handle while pulling.
3. If it’s still stuck, use a handle puller (available at hardware stores) or gently tap around the base of the handle with a wooden mallet.
4. As a last resort, you can try applying gentle heat with a hairdryer to expand the metal slightly.

Remember, patience is key here—forcing a stuck handle can damage other components.

Accessing and Removing the Cartridge

1. Once the handle is removed, you’ll likely see a decorative trim sleeve or escutcheon. This usually unscrews or pulls straight off.
2. Next, you’ll see the cartridge retaining nut or clip. For a nut, use an adjustable wrench to loosen it counterclockwise. For a clip, use needle-nose pliers to remove it.
3. With the retaining mechanism removed, grasp the cartridge stem with pliers and pull it straight up and out. It might require some wiggling, but don’t twist or you could break it.
4. If the cartridge is stuck, apply penetrating oil around its edges and wait before trying again.

Inspecting and Replacing the Cartridge

1. Examine the old cartridge for damage, mineral buildup, or worn O-rings.
2. Clean the faucet body housing with a cloth and vinegar to remove any mineral deposits.
3. Compare your old cartridge with the replacement to ensure it’s an exact match.
4. Apply a small amount of plumber’s grease to the O-rings on the new cartridge.
5. Align the new cartridge in the same orientation as the old one was installed. Most cartridges have alignment features like tabs that must be positioned correctly.
6. Press the new cartridge firmly into place, making sure it’s fully seated.

Reassembling Your Faucet

1. Replace the retaining nut or clip, tightening securely but not over-tightening.
2. Reinstall the trim sleeve or escutcheon.
3. Reattach the handle, making sure it’s properly aligned.
4. Tighten the handle screw and replace the decorative cap.
5. Turn the water supply back on.
6. Test your faucet by running it through the full range of temperatures and ensuring there are no leaks.

Troubleshooting Common Issues

What to Do If the Leak Persists

If your faucet is still leaking after replacing the cartridge:

1. Check for proper alignment: The cartridge might not be fully seated or aligned correctly.
2. Inspect the faucet body: Look for cracks or damage that might be causing leaks.
3. Examine the valve seat: If it’s corroded or damaged, water may continue to leak.
4. Verify water pressure: Excessive water pressure can cause leaks even with new parts.
5. Consider replacing additional components: Sometimes the spout O-rings or other seals need replacement too.

Preventative Maintenance Tips

To prevent future leaks and extend the life of your faucet:

1. Avoid using excessive force when turning the handle on or off.
2. Clean your faucet regularly to prevent mineral buildup.
3. Address small leaks promptly before they become bigger problems.
4. Consider installing a water softener if you have hard water, as mineral deposits can accelerate wear.
5. Apply silicone lubricant to the cartridge O-rings every few years.

When to Call a Professional

While most single-handle faucet repairs are DIY-friendly, there are times when calling a professional makes sense:

• If you discover corroded or damaged water pipes
• If the faucet body itself is cracked or damaged
• If you’ve attempted the repair but the leak persists
• If your plumbing system has unusual configurations
• If you’re uncomfortable working with plumbing fixtures

Remember, there’s no shame in calling a pro—sometimes their expertise can save you time and prevent costly mistakes.

Frequently Asked Questions

1. How much water does a leaky bathtub faucet actually waste?

A faucet that drips just once per second can waste over 3,000 gallons of water per year. That’s enough to fill about 60 bathtubs! The faster the drip, the more water is wasted, and the higher your water bill climbs.

2. How can I identify my faucet brand and model to get the right replacement cartridge?

Look for branding on the handle, escutcheon plate, or faucet body. If you can’t find any markings, take clear photos or bring the old cartridge to a plumbing supply store. Professionals there can often identify the brand and recommend the correct replacement part.

3. My water has a reddish tint after fixing the faucet. Is this normal?

A reddish tint usually indicates rust in your pipes, which can be disturbed during repairs. Run the water for a few minutes to clear the lines. If the discoloration persists for more than an hour, you may need to investigate further as it could indicate corrosion issues in your plumbing.

4. How often should bathtub faucet cartridges be replaced?

Cartridges typically last 15-20 years, but this varies based on water quality, usage, and faucet quality. Hard water with high mineral content can significantly reduce cartridge lifespan. Replace your cartridge when you notice leaking, difficulty adjusting temperature, or stiffness in the handle movement.

5. Can I repair my cartridge instead of replacing it?

While it’s sometimes possible to clean and refurbish a cartridge by replacing just the O-rings and seals, full replacement is usually more reliable and not much more expensive. Cartridge repair kits are available for some brands, but for a long-term fix, installing a brand new cartridge is typically your best bet.

Conclusion

Fixing a leaky single-handle bathtub faucet is a satisfying DIY project that can save you money and conserve water. By understanding your faucet type, gathering the right tools and materials, and following this step-by-step guide, you can silence that annoying drip and enjoy a properly functioning faucet once again.

Remember that the key to success lies in careful disassembly, proper identification of replacement parts, and methodical reassembly. Take your time, stay organized, and don’t hesitate to take photos as you go to make reassembly easier.

With the knowledge you’ve gained from this guide, you’re now equipped to tackle this common household repair with confidence. Happy plumbing!