How to Install an Electric Outlet in a Concrete Floor

A nice thing about being a homeowner is the ability to add improvements where you see fit. This can include just about anything, including installing an electrical outlet in a concrete floor. The challenging part of this project isn't the wiring, but having to cut through the concrete. But, with the right tools and safety precautions, the job can be completed by the determined DIYer.

Cutting the Concrete

Step 1

Locate the nearest junction box where you will be connecting the new electric outlet. Junction boxes are about 4 inches square and usually mounted on the outside of the wall in concrete areas, such as basements.

Step 2

Draw a line from the junction box or outlet to where you want the new outlet to be located in the concrete floor with a contractor crayon. Lay the outlet box on the floor in your chosen location. Mark around the outside of the box and set aside.

Step 3

Attach a spade concrete cutting bit to the end of an electric jackhammer. Put on the proper safety equipment, including work clothes, gloves, goggles and a helmet. Place the edge of the spade on the ground at the start of the line. Turn on the jackhammer and break up the concrete along the line. You only need to make the trench wide and deep enough for an electric conduit.

Step 4

Work your way down the maker with the jackhammer, breaking up the concrete as you work. Make a larger hole at the end of the line for the outlet.

Step 5

Clean up the concrete debris with a broom and shopvac.

Wiring the Outlet

Step 6

Turn off the electricity at the main circuit breaker for the circuit that controls the junction box. Loosen the screws holding the cover of the junction box in place with a screwdriver and remove.

Step 7

Measure out the distance between the junction box and the outlet. Use a pair of snips to cut off the same amount of conduit.

Step 8

Run wires through the conduit so they poke out at either end.

Step 9

Loosen the retaining screw at the bottom of the junction box. Knock out the plug with a screwdriver if needed. Thread the wires from the conduit into the junction box and pull the conduit up tight against the junction box body in the retaining outlet. Secure in place by tightening the retaining screw.

Step 10

Connect the black wire from the conduit run to the black wire inside the junction box, the white wire to the white wire in the junction box, and the bare copper wire to the bare copper wire inside the junction box or the grounding screw (if the copper grounding wire isn't present). Replace the junction box cover.

Step 11

Knock out the plug in the side of the outlet box. Thread the wires and conduit into the outlet as you did with the junction box. Secure with the retaining screw. Lay the outlet box into the opening in the concrete so the opening is facing upwards.

Step 12

Loosen the terminals on the side of the outlet. Connect the black conduit wire inside the junction box to the terminal marked "Live" on the terminal, the white wire to the terminal marked "Neutral" on the outlet, and the copper wire to the green grounding screw. Gently press the outlet into the outlet box and secure with screws on the top and bottom. Replace the outlet in the hole.

Step 13

Restore power to the electrical circuit. Use a voltmeter to test the outlet for power. If the meter doesn't move, recheck your wiring connections.

Step 14

Mix concrete according to the manufacturer's instructions and pour into the trench to cover the conduit and around the outlet box. Take care not to get any concrete into the outlet box.

Step 15

Restore power to the electrical circuit. Replace the cover of the outlet box.