Installing the Crown Molding Lighting Circuit

• Install Crown Molding Lighting
• Crown Molding Installation
• Trim Molding Guide
• Custom Trim Molding Ideas

These instructions cover installing the electrical circuit, switch and receptacle for the crown molding lighting project. For placement of the new outlet box and installing the molding, go to the other page of this article.

The lights in this project are plugged into an electrical receptacle located behind the molding. The power to the receptacle is controlled by a wall switch. To allow for dimming the lights we use a rheostat for added effect in this dining room.

If no wall switch and light exist in the room where you are adding crown molding lighting go to finding an electrical source for help finding a source and adding the wiring required to power the new lighting. If the room already has a switch and light fixture, use the instructions below to modify the circuit to serve both the existing lights and the new outlet.

Tap an Electrical Source

Check the existing switch to determine if there is an always hot source wire. First check the black wire that appears to serve the switch, usually the bottom terminal. Test for 120 volts at this switch terminal by touching it with a probe while the lights are off. If the wire is not hot, check the other terminal and any other black or red wires in the box.

When you have a hot wire, shut off the power and remove the screws holding the existing switch to the box. Mark the wires so you can identify them later and remove them from the switch. Remove the switch box and pull the wires free.

Install the Outlet Boxes

If you can remove the existing switch box without damaging the wall you can use an old work outlet box to replace it. If you have to damage the wall to get the box out, you will have to use a nail–in box or one with a bracket to attach it to the wood framing and repair the wall when you're done.

Use an old work box for the receptacle and locate it in the same hollow part of the wall as the current switch box. Place the box horizontally so it will be hidden behind the new crown molding. Mark the wall using the new boxes to draw an outline for the holes and cut drywall using a drywall saw. Cut wood lath plaster with a keyhole saw or reciprocating saw. Run the new cable from the switch hole to the receptacle hole and push the wires into rear of the new outlet boxes before installing them in the wall.

Install the Switches

Reinstall the switch and add a second switch to the circuit to control the new lighting. We use a rheostat here, but you can use a simple single pole switch also. Split the source to serve the two switches by splicing the hot wire to two short pieces of jumper wire using the proper wire gauge. Connect each jumper wire to the bottom terminal on one of the switches.

Reconnect the other wires to the original switch and then wire the new one. Connect the top terminal to the black wire from the new cable. Splice the white wire from the new cable with the other white wires in the box. Splice the ground wire with the existing ground wires in the box and a short jumper wire connected to the ground terminal on the new switch.

Install the Receptacle

Connect the black wire from the new cable to the hot terminal on the receptacle. Connect the white wire to the neutral terminal and the ground wire to the ground terminal. Install the receptacle in the horizontal outlet box.

Turn on the power to the circuit and test it using a lamp or other light by plugging it into the receptacle and working the switch. Make sure the dimmer is working and then lay the string lights in the space behind the molding and plug them into the receptacle.