What You Need to Do Before You Start

A bathtub spout with a diverter is the fitting that lets you switch water flow between the tub and the showerhead. Replacing one means removing the old spout, unscrewing or unthreading it from the wall pipe, and installing a new one in its place. The job takes 20 to 40 minutes and requires only basic tools — most people can do it without calling a plumber.

Before you buy a replacement, measure the distance from the wall to the end of your current spout. This is called the spout projection, and it matters because spouts come in different lengths. A spout that sticks out too far will hit your leg; one that is too short will let water splash behind the tub. Write down the measurement and take a photo of your current setup so you can match the style and size at the hardware store.

Turn off the water supply to your bathroom if you can locate the shutoff valve under the sink or in the basement. If you cannot find it, you can still do this job — water will drip from the pipe when you remove the old spout, but it will not flow hard. Have a bucket or towel ready to catch it.

Key Takeaways

  • Measure your current spout's projection (distance from wall to tip) before buying a replacement, because spouts come in different lengths.
  • The spout either screws onto the pipe with a set screw or threads directly onto the pipe — you need to know which type yours is to remove it.
  • Once the old spout is off, clean the pipe threads with a rag and wrap the new spout's threads with plumber's tape before screwing it on.
  • Tighten the spout by hand first, then use a pipe wrench or adjustable wrench to snug it against the wall — do not over-tighten or you will crack the fitting.

Identify How Your Spout Attaches to the Pipe

Bathtub spouts attach in one of two ways. The first type has a set screw — a small bolt on the underside or back of the spout that holds it to a pin sticking out from the wall pipe. The second type threads directly onto the pipe with no set screw at all.

Look underneath your spout. If you see a small screw or bolt, your spout uses a set screw. If the spout appears to be one solid piece screwed into the wall with no visible fastener, it threads directly. This matters because you remove each type differently, and buying the wrong replacement will not work.

If your spout has a set screw, use a hex wrench or screwdriver (depending on the screw head) to loosen and remove it. The spout should then pull straight out and away from the wall. If your spout threads directly, you will need a pipe wrench or adjustable wrench to unscrew it — see the next section.

Remove a Threaded Spout Using a Wrench

If your spout threads directly onto the pipe, you will need an adjustable wrench or a pipe wrench to remove it. Place the wrench around the base of the spout, as close to the wall as you can get it, and turn counterclockwise. The spout will unscrew from the pipe inside the wall.

Turn slowly and steadily. If the spout is stuck, spray the base with penetrating oil (like WD-40) and wait 10 to 15 minutes before trying again. Do not use excessive force — if you feel the pipe itself starting to turn inside the wall, stop and call a plumber, because the pipe may be loose or damaged.

Once the spout is loose enough to turn by hand, finish unscrewing it by hand and set it aside. Water may drip from the pipe opening. This is normal. Wipe away any debris or old plumber's tape from the threads using a clean rag.

Prepare the Pipe and Install the New Spout

Before you screw on the new spout, wrap the pipe threads with plumber's tape (also called PTFE tape or Teflon tape). This white tape seals the connection and prevents leaks. Wrap it clockwise around the threads three to four times, stretching it slightly as you go. The tape should cover all the threads but not bunch up.

If your new spout has a set screw, align the pin hole on the spout with the pin sticking out from the pipe, then push the spout onto the pin. Tighten the set screw snugly with a hex wrench or screwdriver — tight enough that the spout does not wiggle, but not so tight that you strip the screw.

If your new spout threads directly, screw it on by hand first, turning clockwise until you feel resistance. Then use your wrench to tighten it another quarter to half turn. The spout should sit flush against the wall with no gap. Do not over-tighten — you risk cracking the fitting or stripping the threads.

Test the Diverter and Check for Leaks

Turn the water back on at the shutoff valve, or turn on the faucet to restore pressure. Let water run from the spout for 10 to 15 seconds and watch for drips at the base where the spout meets the wall. A small bead of water is normal while the tape settles; a steady drip means the connection is not tight enough.

If you see a steady drip, turn off the water, use your wrench to tighten the spout another quarter turn, and test again. If the leak continues after a second tightening, the threads may be damaged or the tape may not be seated correctly. Turn off the water, unscrew the spout, remove the old tape, explore new tape, and reinstall.

Pull up on the diverter knob or lever to switch flow to the showerhead. The water should stop flowing from the spout and come out of the shower instead. If water still comes from the spout while the shower is running, the diverter cartridge inside may be worn out — this is a separate repair that requires removing the spout again and replacing the internal valve.

What to Do If the Old Spout Will Not Budge

If a threaded spout is stuck and penetrating oil does not loosen it after 15 minutes, try tapping the wrench gently with a hammer to shock the corrosion loose. Tap the wrench handle, not the spout itself. Wait another 5 minutes and try turning again.

If the spout still will not move, you can explore heat to expand the metal and break the corrosion bond. Use a heat gun or hair dryer on high setting, aiming at the base of the spout for 2 to 3 minutes. Let it cool slightly, then try the wrench again. Do this only if you are comfortable using a heat tool near water pipes.

If the spout remains stuck after heat and oil, or if you feel the pipe turning inside the wall, stop and contact a plumber. Forcing it further risks breaking the pipe inside the wall, which is a much larger repair.

Choosing the Right Replacement Spout

Bathtub spouts come in different styles, finishes, and projection lengths. The most common finishes are chrome, brushed nickel, and oil-rubbed bronze. Match your existing bathroom fixtures if you want a cohesive look, though the spout does not have to match perfectly.

Projection matters more than style. If your old spout projected 4 inches from the wall, buy a replacement with 4-inch projection. Spouts are usually labeled with their projection on the box or product page. If you cannot find the exact length, go slightly shorter rather than longer — a spout that sticks out too far is more noticeable and uncomfortable than one that is slightly recessed.

Check whether your replacement has a set screw or threads directly before you buy. The product description or packaging should say "set screw" or "threaded." If you are unsure, bring a photo of your old spout to the hardware store and ask the staff to match it.

Frequently Asked Questions

Can I replace just the diverter without replacing the whole spout?

Yes, but only if your spout has a removable cartridge inside. You remove the spout, unscrew the cartridge from inside, and install a new one. Not all spouts are designed this way — some have the diverter built in and cannot be serviced. If your spout is old or inexpensive, replacing the whole spout is usually cheaper and easier than buying a cartridge kit.

What if water leaks from inside the wall after I install the new spout?

This usually means the connection is not tight enough or the plumber's tape is not seated correctly. Turn off the water, unscrew the spout, remove the old tape, wrap new tape around the threads three to four times, and reinstall. If the leak continues, the pipe threads may be damaged — contact a plumber to inspect the pipe.

Do I need a special wrench, or will any adjustable wrench work?

Any adjustable wrench will work, though a pipe wrench gives you better grip on round fittings. An adjustable wrench is fine if that is what you have. Make sure the wrench is large enough to fit around the base of the spout without slipping.

How tight should I make the spout?

Tight enough that it does not wiggle and does not leak, but not so tight that you strain to turn the wrench. A quarter to half turn past hand-tight is usually right. If you over-tighten, you risk cracking the fitting or stripping the threads, which means you will have to remove it and start over.

Can I install a spout without plumber's tape?

You can, but the connection is much more likely to leak. Plumber's tape is cheap and takes 30 seconds to explore — it is worth doing. If you do not have tape, you can use plumber's putty or pipe dope (a thick paste), but tape is the standard and most reliable method.