Eliminate those ugly and often dangerous extension cords. You can add a new outlet quickly and easily without tearing open a wall, if you already have an outlet in the other side of the wall. No extra holes. No messy patching and repainting. The procedure we show here allowed us to center our TV against a wall in the family room that had no outlet. Since there was already an outlet in the other side of that same wall (facing into an adjacent bedroom), we just added a new outlet in the family room, drawing power from the bedroom outlet.
A remodeling box has “wings” which open and clamp the box to the drywall. Cut your hole to exactly fit the box.
This technique only works if you can use an outlet as a power source that’s opposite, or nearly opposite, the place where you want your new outlet. To determine whether you can safely use an existing outlet, follow the list below.
Always confirm the required box size with your local building inspector. In most regions, you have to obtain an electrical permit for this work from your local building department. This helps ensure a safe job.
TURN OFF the power at the main panel, unscrew the outlet and use a voltage tester to double-check that the power is off. With either lead touching a ground wire (bare copper), touch the other lead first to the neutral terminals (silver colored), then to the hot terminals (gold colored). If the light glows with either contact, the circuit is still live. Find the right breaker and turn it off.
FEED a length of new cable through one of the knock-out holes at the back of the existing box (punch out the hole with a screwdriver). Feed through enough cable to reach the new box (Photo 4), plus an extra foot. Use 14-gauge wire for a 15-amp circuit.
STRIP about 10 in. of plastic sheathing from the new cable to expose the black, white and copper wires. Run the new cable, with sheathing, at least 2 in. up inside the box, and double over the excess wires to help hold the cable in place. Strip 5/8 in. of insulation off the ends and connect the wires from the new cable to the existing bundles—white to white, black to black, ground to ground. Use new wire connectors of adequate size for the four wires in each bundle.
MARK the opening for the new box and cut it out with a drywall saw. Fish for the new cable with a hook made from a wire coat hanger. Pull the cable through the opening cut in the wall. Then strip about 9 in. of sheathing off the end of the cable, insert the cable so the sheath extends about 1 in. into the box and mount the box in the wall as shown in Photo 5.
CONNECT the new wires to the new outlet: white (neutral) wire to a silver-colored terminal screw; black (hot) wire to a gold-colored terminal screw; bare wire to the green grounding screw. Make sure the cable sheath remains secured inside the box.
Once you’ve determined the outlet that you’ll use as a power source and have shut it off, use an electronic stud finder to locate the studs on both sides. You can put your new outlet anywhere between these two studs.
Hold the face of the new electrical box against the wall where you want it to go, and trace around it with a pencil. Cut out the hole with a drywall saw. Note: Be sure to buy a “remodeling” box that can be secured to the drywall, not one that must be mounted on a stud.
Next, unscrew the existing outlet on the other side of the wall from its box (Photo 1) and punch out one of the knock-outs at the back of the box using a screwdriver. Then feed the new cable through the knock-out into the wall cavity (Photo 2). Feed in enough cable to reach the new outlet location—plus about 1 ft. Connect the wires of the new cable to the existing wires (Photo 3). Pull the cable out through the new outlet hole in the wall (Photo 4) and feed it into the new box. Then mount the new box in the opening. Photos 3 and 5 show how the electrical connections are made. Finally, call the electrical inspector to check your work.
Before you tackle any part of this project, turn off the power to the circuit at the main electrical panel by switching off the breaker or removing the fuse.
Have the necessary tools for this DIY project lined up before you start—you’ll save time and frustration.
Avoid last-minute shopping trips by having all your materials ready ahead of time. Here's a list.