Installing Ground Fault Circuit Interrupter Outlets

An outlet half-way through installation
Fstop123/Getty Images

To better understand what is involved in installing a ground fault circuit interrupter (GFCI) in your home, you’ll first need to have an understanding of basic electrical wiring. If you feel at all uncomfortable about working on an electrical circuit, then it might be best the call a professional. Understanding basic circuitry, knowing where to turn circuits off and on, being able to test circuits and keep track of what goes where are all essential and important.

As with all electrical projects, be sure to turn the power off to anything you are working on. Electrical safety should always be number 1 on your list. This isn't a difficult project, and it shouldn't take more than 15 minutes.

Tools and Supplies You'll Need


Turn Off the Power

Before you begin any electrical project, go to the electrical panel and shut off the circuit that you’ll be working on. Sometimes, not always, the electrician will mark the panel, on the inside of the door with the location that each individual breaker supplies. If it is marked, turn off the correct circuit. If it is not marked, plug something into the circuit and one-at-a-time start shutting off breakers. When the device that you plugged in goes out, you may have found the circuit.

Check the Circuit

Always double-check the circuit with a tester or meter to be safe. Never assume that, just because the light went out, the circuit is off. Maybe, just maybe the bulb burned out, and you happened to be at the right place at the wrong time.

Mark Each Wire

Now that the circuit is safe to start work, you must remove the existing outlet cover and then the outlet. Do yourself a favor and get a pencil and paper so that you can mark down how everything is connected. If you have a roll of masking tape, markdown things like “right top side hot wire,” and you’ll be able to place these right on the wires themselves. Use the tape and label each wire, paying close attention to what color screws each connect to. This will eliminate any guesswork when installing the new device.

Replace the Outlet

This step is unusually specific. A regular outlet has two hot and two neutral terminals. These are common, meaning you can connect to either of the two screws for the "hot" or "neutral" connection. For the GFCI outlet, things get a little more interesting. There are two separate connections, line and load connections. The power comes in on the "line" connection and out on the "load" connection. Unscrew the wires from the outlet and remove. If you’re reusing the existing wire feed, connect the new device to the GFCI outlet. The brass terminal is for the “hot” wire. This is usually the black or red wire. Connect the white wire to the silver screw. This is a neutral connection. The bare or green wire is the ground connection. Place it around the green screw. When you have connected all the wires successfully, give the entire side of the outlet a wrap of electrical tape. This will eliminate the screw from touching either the side of the box or a stray wire when reinstalling.

Install the Outlet

Press the outlet into the box before installing the outlet with the screws provided. You may have to carefully push and bend the wires back into the box to make everything fit. Now install the cover plate that came with the outlet, and your installation is complete.

Turn on the Power and Test

Once you’re satisfied, go back to the electrical panel and turn on the circuit. Go to the GFCI and press the reset button. Now use your tester to check the circuit. You can also use a lamp or any small appliance to see if power is restored.

Note: Always make sure that the power is off before performing any electrical project.