How to Convert a 3-Handle Shower Faucet to a Single-Handle Valve

How to Convert a 3-Handle Shower Faucet to a Single-Handle Valve

Advanced
30 min
7 Steps
42 items

This project involves replacing an outdated three-handle (hot, cold, diverter) shower and tub faucet with a modern single-handle, pressure-balancing valve. The process requires accessing the plumbing within the wall, removing the old valve body, re-plumbing the hot and cold water lines to a new valve, and then repairing the wall and installing the new faucet trim.

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Best for advanced DIYers and professionals with basic plumbing knowledge and familiarity with power tools. Requires HDX Over the Glass Indoor Safety Glasses VS-265 and StoneBreaker X-Large Operator Work Gloves SB_AM_OPE_BR_XL and MCR Safety BearKat Safety Glasses MCSCRWBK110.

Tools & Materials

RSI 7.8 ft. x 12 ft. Blue 88% Shade Protection Knitted Privacy Cloth PF-812-BLUE

RSI 7.8 ft. x 12 ft. Blue 88% Shade Protection Knitted Privacy Cloth PF-812-BLUE

The Riverstone line of privacy shade cloths is designed to offer easy to use, shade producing cloth that is UV stable and will last for several years in the hottest environments. All our knitted shade

Safety Glasses

Safety Glasses

Keeps eyes safe from potential hazards.

Zircon StudSensor HD35 Stud Finder 65944

Zircon StudSensor HD35 Stud Finder 65944

The StudSensor HD35 stud finder features a bright, easy-to-understand interface. A wide, contoured grip for comfort and ease of use, provides optimized visibility and a secure hold at any angle. Find the edges of wood and metal studs to securely anchor pictures, mirrors, and shelves to the wall while also avoiding live AC electrical wiring.

Common Problems

Hold on to the valve when making the last cut so it doesn't drop.

Solution: To avoid this issue: Be mindful of this warning and take appropriate precautions.

Cutting too close to fittings risks damaging pipes and making valve installation impossible.

Solution: For copper pipes, cut midway between the valve and any elbow fittings to leave enough pipe for the new installation.

Use two wrenches working in opposite directions to avoid twisting and damaging the water pipes inside the wall.

Solution: To avoid this issue: Be mindful of this warning and take appropriate precautions.

Double-check that the water is completely off before cutting any pipes. Open a lower-level faucet to drain the lines.

Solution: To avoid this issue: Be mindful of this warning and take appropriate precautions.

Water spills onto the floor when pipes are disconnected.

Solution: Have a bucket or towels ready to catch any residual water in the pipes.

Carefully follow the manufacturer's instructions to ensure the valve is set at the proper depth. If it's too deep or too shallow, the trim will not fit correctly.

Solution: To avoid this issue: Be mindful of this warning and take appropriate precautions.

The shower valve won't work if the tub drop outlet isn't 1/2' copper pipe.

Solution: The tub drop outlet must be 1/2' copper pipe for the valve to function properly.

Frequently Asked Questions

How challenging is this conversion for an intermediate DIYer, and what's a realistic time frame?

This project is rated intermediate due to the necessary plumbing and wall repair. While feasible for a dedicated DIYer, expect it to take a full weekend or several evenings, especially if you encounter unexpected plumbing configurations or need to learn new techniques. Adequate planning and preparation can significantly reduce the overall time.

Always shut off the main water supply to your house before starting any work to prevent flooding. Wear eye protection when cutting pipes or using power tools. Before cutting into walls, use a stud finder and potentially a non-contact voltage tester to avoid electrical wires or hidden pipes, which could cause injury or damage.

A common mistake is not fully draining the lines after shutting off water, leading to unexpected drips. Another is failing to adequately test for leaks before repairing the wall, which can cause significant damage later. Ensure all new connections are tight, test the system thoroughly for at least an hour before closing up the wall, and double-check pipe routing for any potential strain.

Yes, specific tools like the GEARWRENCH Mini Tubing Cutter and Husky Reamer are crucial for clean copper pipe work. Push-to-connect fittings (e.g., QUICKFITTING) are highly recommended as they significantly simplify plumbing connections, eliminating the need for soldering tools and skills. This makes the project much more accessible and faster for DIYers while providing reliable seals.

Plan your opening carefully by locating the studs around the existing valve and making a precise, rectangular cut, ideally between two studs. Aim for an opening large enough to comfortably work within, but no bigger than necessary, as you'll need to repair it later. Consider framing out the opening with 2x4 lumber for an access panel for future maintenance.

Yes, PEX piping is an excellent alternative to copper for this type of plumbing and is often easier for DIYers to work with due to its flexibility. If using PEX, you would need a PEX crimp tool or an expansion tool, along with the appropriate PEX fittings instead of copper fittings. Ensure compatibility with your chosen valve body.

The primary advantages are enhanced safety, comfort, and modern aesthetics. A pressure-balancing valve prevents sudden temperature changes (scalding or freezing bursts) if someone flushes a toilet or turns on another faucet elsewhere in the house. It also offers easier, single-control operation for both water flow and temperature, and a sleeker look.

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30 min | 7 Steps