How to Replace a Bathtub or Shower Faucet

To protect the finish while you work, wrap a cloth around the connection first. Remove the shower head using a pair of pliers, turning counterclockwise. Hold the shower arm with your free hand to prevent any movement inside the wall. Once all the way loosened, remove the shower head from the shower arm.

Depending on the handle, you’ll either pry off the cover plate with a screwdriver or find the set screw in the handle and use an Allen wrench to unscrew it, then remove. Once the handle is removed, unscrew the trim plate against the wall and remove it and all other parts until you’ve reached the valve inside the wall.

Locate your shower valve by cutting a section of drywall on the other side of the wall from your shower valve, about a foot square. If you happen to have an access panel to the valve and pipes, simply remove the cover. The valve is mounted to a stringer, a piece of board that runs between the wall suds. 

Along with the valve you’ll find three copper pipes. One goes up to the shower head and the other two to the hot and cold lines. Cut the pipes with a tube cutter. Once the pipes are cut, use a reciprocating saw to detach the stringer from the studs. The valve, which is attached to the stringer, will come with it. 

Clean the ends of the freshly cut pipes. You may need to deburr them first before attaching any connectors. Use a deburring tool to smooth the cut edges, then clean with a cloth. Attach female adapters to the ends of each. On the new valve, there will be outlets for connecting to the shower pipe and hot and cold lines. For tub and shower combos, the valve will have outlets for the water lines and for the pipes to send water up to the shower head and down to the spout. Wrap the ends of the outlets with plumber’s tape and attach connectors.

Attach the valve to the stringer and place it back in the wall, where you’ll reconnect it to the pipes. Make sure that the valve comes out the correct distance from the wall. This will help ensure the new faucet fits correctly. Refer to the manufacturer’s instructions for the dimensions to set the correct depth. Factor in the thicknesses of the drywall and the tile or insert when setting the depth. 

Once everything is back in the wall, turn the water back on and check the connection for leaks.

After you’ve made sure there’s no leaking, repair the drywall. To make things easier to access in the future, consider covering the opening with an access panel instead of patching the drywall.

Install the cartridge. Screw off the bonnet nut and set it aside; you’ll need it later. Take off the test cap and the debris screen, discarding both. Find the “H”, which stands for hot. It’s usually on the left. Line up the “H” on the hot side. Line up the keys, which look like arrows. Everything should fit snugly if inserted correctly. Add the bonnet nut back on. 

Slide the sleeve that came with the shower faucet handle over the cartridge. Add the escutcheon, the plate that covers the rough opening, over the cartridge.

Place the handle over the cartridge, but don’t tighten it yet. To prevent scalding, you’ll need to check the water temperature first. Turn the water back on and turn the handle all the way to the hottest position. Fill a glass with water from the faucet and use a thermometer to check the temperature. The water coming out shouldn’t be hotter than 120 degrees. If it’s too hot, take the handle off and locate the temperature limit stop. Adjust the temperature and recheck. You may need to check your water heater to ensure it’s set to 120 degrees. Make sure to follow the manufacturer’s instructions. 

With the water temperature set to the safest setting, use an Allen wrench to tighten the set screw on the handle.