Older shower valves will leak over time. But, sometimes, it’s safer to replace them with a pressure-balanced shower valve rather than fix them. When a homeowner knew that an upgrade would mean making holes in his perfectly preserved bathroom, he reached out to Richard Trethewey for help.
How to Repair a Leaking Shower Valve
- Turn off the water to the shower. If there are isolation valves nearby, shut them and test the shower to ensure that they’re off. Otherwise, you may need to shut off the water at the valve where it comes into the home.
- Remove all of the trim on the shower valves and tub spout. Use water pump pliers to grip the trim pieces and unthread them so that the shower valves can slide through the wall once they’re cut loose.
- Gain access to the back of the shower valve. Use a sand screen to clean up the copper pipe. Sand the pipes that go to the hot and cold side of the valve, the tub spout, and the showerhead. Use a tubing cutter to cut the pipes in the cleaned areas.
- If the shower valves are mudded into the tile wall, you’ll have to chip them loose. Using a masonry chisel, carefully chip the hardened plaster away from the back of the shower valves until they’re loose.
- On the inside of the shower, place a scrap board across all three valves and tap the board with the hammer. This should loosen the valves and allow them to be removed from the back side of the shower.
- Place the new cover plate over the existing valve holes. Be sure to leave enough room for the tub spout and move the plate up if necessary. Trace the outside of the plate on the shower wall with a pencil. Remove the plate, install the template, and mark the shower.
- Use a hammer drill and masonry bit to drill a series of holes around the outline of the template. Then, cut from hole to hole with the oscillating tool to remove the tiles and wallboard or plaster and lathe behind it.
- Hold the new shower valve so that it’s centered in the hole in its new location. Take measurements for the various pieces of copper pipe and fitting you’ll need. Cut these pieces and test fit the valve. Also, use the pump pliers to remove the spindle from the front of the valve.
- Disassemble the test-fit pieces and apply flux to the joints. Reinstall the shower valve with the copper pieces. Heat the joints with a torch and apply lead-free solder to the joints to secure everything in place.
- On the inside of the shower, replace the spindle and tighten it in place. Slide the cap over the spindle and tighten it. Then, place the new cover plate over the shower valve, line up the diverter valve, and tighten it in place with the supplied screws. Install the handle.
- Turn the water back on and check for leaks.
Richard uses an imp tubing cutter to easily cut the connecting water pipes and remove the old shower valve.
He then lays masking tape around the 3 valve openings and traces out a template of the cover plate.
Richard assembles the new pressure-balancing shower valve by cleaning out the fittings and the exterior of the pipes with a wire brush. Then, applying a layer of flux to the interior fittings and exterior of the pipes. He installs the valve by heating up the pipe along the joints using a torch and soldering them securely to the water lines.
All supplies used for this project can be found at most home centers.
- Masking tape
- Sand screen
- Scrap wood
- Pressure-balancing shower diverter valve
- Oversized cover plate
- Copper piping and fittings