DIY Network

Add an Electrical Switch

Install a second switch in an existing switch box.

More in Electrical

  • Time

    2 hours

  • Price Range

    $1 - $50

  • Difficulty



Step 1: Remove the Existing Switch Box

Shut off the power at the main circuit panel (Image 1).

Use an electrical tester to be sure that the power is off at the fixture.

Disconnect the wires to the old single-pole switch (Image 2).

Disconnect the wiring cables from the box.

If the old box is attached to a wall stud with nails or screws, use a pry bar or screwdriver to remove it.

Step 2: Install a Double Switch Box

Secure the new double box to the wall stud.

old switch box is repalced with new double switch

Courtesy of Jeffrey Rowe

Step 3: Connect the Old and New Switches

Pull the existing switch wiring cables, and the wiring cable (or cables) for the fixture controlled by the new switch, into the box through separate rear access holes (Image 1). Secure the cables to the box with clamps.

Use a barrel clamp to connect the bare or green ground wires from both incoming cables.

Replace the wires to the old switch just as they were attached before.

Attach the incoming fixture wires to the new switch. This connection will depend on how the power is routed to the fixture controlled by the switch.

Install the double switch box cover (Image 2).

Restore power to both circuits and test the operation of both switches.