Kitchen cabinet lighting, also known as task lighting, is an inexpensive way to upgrade the appearance of your kitchen. The hidden lights, when connected to a dimmer switch, allow the homeowner a convenient way to adjust the lights as needed. This not only provides additional lighting for food preparation, but also adds a dramatic accent to your kitchen decor.
1. Locate a suitable power source for your cabinet lights. The easiest way to achieve this is by using the power from an existing single-gang outlet located underneath an upper cabinet in the back splash area.
2. Turn off the power supplying the outlet box and test it to make sure it is indeed off. A voltage meter or plugging in a small appliance is the best way to verify that the power is off.
3. Remove the outlet by using a screwdriver to extract the mounting screws securing the cover plate and outlet to the electrical box. You will also need to disconnect the wires connected to the outlet by using a screwdriver or cutting them close to the receptacle with a pair of wire cutters.
4. Align an old-work two-gang electrical box over the existing single-gang box and trace the outline with a pencil. Make sure that your double-gang box extends away from the stud securing the single-gang box. Old-work boxes are designed to replace existing boxes. Two mounting screws, one in each diagonal corner, secure the old-work box to the wall.
5. Cut the outline of the double-gang box with a keyhole saw. Place a flat pry bar between the stud and the single-gang box to pry it loose and remove.
6. Install the light fixture box underneath the cabinet in the desired location. There are various styles of under-cabinet lighting with different mounting styles. Mount the light fixture box according to the manufacturer's instructions. Remove the knockout plug in the fixture housing and install a cable connector using a screwdriver or needle-nose pliers.
7. Drill a hole above the opening in the wall and underneath the cabinet behind the fixture box using a 1/2-inch spade bit and drill. You want to drill the hole as tightly against the bottom of the upper cabinet as possible.
8. Run a new length of wire through the hole you drilled in the wall and down through the double-gang hole in the wall, leaving about 8 inches of slack. Walk the wire along the back edge of the cabinet and through the cable connector in the light fixture box and cut using the wire cutters. Be sure to leave an ample amount of slack in the wire to make the connections in the light fixture.
9. Tighten the connector screws on the cable connector using a screwdriver to secure the wire. Strip the outside insulation away from the end of the wire using a utility knife. Remove 1/2 inch of the insulation from the ends of both the black and white wires.
10. Connect the black and white leads from the new wire to the black and white leads for the fixture and secure them using wire nuts. Repeat this step for the green or bare copper ground wires. Install the light fixture bulb and cover it according to manufacturer's instructions.
11. Secure the wire underneath the cabinet using cable staples. Cable staples are designed to hold the wire in place and install easily using a hammer.
12. Install the new double-gang old-work electrical box in the wall opening. Make sure to feed the existing receptacle wire and the new wire from the light fixture through the openings in the box. It may be necessary to pry open the holes in the box with a screwdriver. Push the box into the wall opening and press tightly against the wall while simultaneously tightening the two mounting screws.
13. Strip the outer insulation using a utility knife to expose the individual wires. Bend the end of the black wire from the fixture over to mark it. Use the wire cutters or wire strippers to remove 1/2-inch of insulation from each end of the wires.
14. Make the required wiring connections in the box. Twist the bare copper "ground" wires together along with an additional piece of ground wire that is about 8 inches long and secure them with a wire nut.
15. Twist the two white "neutral" wires together along with an additional piece of white wire, about 8 inches long, and secure with a wire nut. Your box should now include one ground wire, a white lead and two black leads.
16. Install the receptacle by connecting the ground wire to the green grounding screw located on the bottom of the outlet. Connect the remaining white "neutral" wire to one of the two silver mounting screws located on the side of the outlet and them tighten using a screwdriver. Connect the original black wire to one of the two copper mounting screws on the side of the outlet opposite the silver screw. You will need to connect an 8-inch piece of black wire to the remaining copper screw, which will supply power to the dimmer switch. Now that you have finished wiring the outlet, you can secure it to the electrical box with two mounting screws.
17. Install the dimmer switch by connecting the 8-inch lead from the outlet to the black wire labeled "line" on the dimmer switch with a wire nut. Connect the remaining black wire, the one you folded earlier, to the black dimmer switch wire labeled "load" with a wire nut. If the dimmer switch includes a ground wire, it will need to be connected to the ground wires in the electrical box. Once you have connected all of the dimmer switch wires, secure the switch to the box with two mounting screws. Finish the installation by installing the appropriate cover plate and testing the lights.
