How to Repair a Leaky Shower Faucet Valve

One reader whose home was equipped with an electric water heater complained that his leaking shower valve caused his electric bill to triple.

Even more concerning is the shower valve that leaks inside the wall. Over time, water dribbling into the wall can cause dry rot, mold, and structural problems that can be both hazardous and very expensive to repair.

What Causes a Leaky Shower Faucet or Shower Head Drip?

When water drips or drizzles from a shower head, there is a problem with the shower faucet (valve). In most cases, inner seals are worn, or parts have become corroded or clogged with hard water deposits. And the rubber O-rings and gaskets that seal connections between moving metal parts wear down with time and use. When they do, water squirts or drips out. For more, please see How a Shower Works.

Advice for Fixing Leaky Shower Faucets

If you turn off a shower faucet and the water keeps dribbling out of the shower head, a natural instinct is to crank the handle closed as hard as you can. Unfortunately, this may only make things worse. Be sure the faucet handle is turned all of the way off, but don’t over-tighten it! This may damage the valve.

When working on shower faucets, place rags in the tub or shower floor beneath the faucets and over the drain to protect the surfaces and prevent small parts from being dropped down the drain. Before opening up a shower valve, turn off the water supply. In some houses, a shut-off valve is located in the bathroom, near the shower, or in the basement. If you can’t find the shower shut-off valves, turn off the water supply to the entire house.
 

If you have to shut off the water to the entire house, plan and organize ahead of time. Read through all of the instructions and have the tools and materials that you’ll need readily on hand to minimize the time your home’s water will be off—and alert your family. After shutting off the house water, faucets and water-using appliances won’t work but each toilet will have one flush.

After you’ve turned off the water supply, open the bathroom sink faucet to drain any water from the nearby pipes.

There are many types of shower faucet valves. The methods for fixing the leak will depend upon the type of shower valve. In the articles listed below, you will find step-by-step instructions for fixing the major brands of shower faucets.
 

How to Fix a Leaky Two-Handle Shower Faucet

A shower valve that’s operated by two faucet handles—one hot and one cold—is typically a compression faucet, as discussed in the article How a Compression Faucet Works. Leaks in a compression faucet generally occur when a rubber seal or washer wears out over time, allowing water to seep between movable metal parts.

Fixing a compression shower faucet involves disassembling the unit and replacing the defective washers and seals. It’s important to shut off the water supply to the shower, and to protect the surface of the tub or shower floor and cover the drain. Buy a faucet washer kit so you’ll have the necessary replacement O-rings and washers on hand. Browse faucet washer kits at Amazon.

First, feel the water leaking from the tub spout or shower head. If it’s warm, you know that the leak is coming from the hot-water valve. If the water has been dripping for a while and it is cold, the leak is probably coming from the cold-water valve.

1 Start by removing the faucet handle. Methods for doing this will depend upon the faucet’s design. Older or simply-designed faucets often have an exposed screw front and center or a locking screw in the side. Newer and more decorative models of faucets hide the screw beneath a cover cap. With these, you need to pry off the cover cap to expose the screw. If your faucet handle is the type with a cover cap and there is no obvious method of removal, use a very thin screwdriver or pocketknife to pry the cap off. Be careful not to scratch the finish or damage the material.

2 Once you’ve removed the cover cap, use a screwdriver to unscrew the locking screw, turning it counterclockwise. Remove it and set it aside. Then wiggle and pull on the handle to extract it from the faucet body. This can be difficult to do. You can buy a faucet puller, or improvise with a screwdriver as shown in the video below. 

3 After removing the handle, remove the trim and the sleeve that fits over the faucet stem. You’ll need a plumber’s deep socket, as shown in the video, to extract the faucet stem from the valve body (you can find an inexpensive set online). Fit it over the stem’s hex nut and turn it counterclockwise to unscrew the assembly. At first, you may need to apply significant force to break it free. Unscrew the faucet stem and pull it out of the valve body.
 

4Replace all faucet washers, O-rings, seals, and the flat washer at the end of the stem (remove the screw to replaced the washer).

5 Then reverse the procedures to replace the faucet stem in the valve body. Before you put it in, lubricate the threads with plumber’s grease. Tighten it in the valve body. Temporarily put the handle back on, turn on the water supply, and test the valve. Then finish reassembly. Finally, seal the trim to the wall with tub caulk.