How to Install an Exterior Electrical Outlet
Tap into an existing line with these step-by-step instructions.
If your home doesn't have an outside electrical outlet, it's a simple matter to install one yourself. Here's how to do it:
Materials and Tools:
assorted bits, including an extra-long bit to reach through the exterior wall
exterior GFCI outlet
weatherproof box-to-house outlet
exterior-rated electrical cable
- From the circuit-breaker box, shut off power to the line you'll be tapping into.
- Test the interior outlet with the circuit tester to make sure the power is off.
- Remove the outlet cover and receptacle. Disconnect the wires from the terminal screws, and push the wires out of your way.
- Wearing safety goggles, drill through the back of the electrical box with a bit long enough to reach through the exterior wall. Be sure there are no obstructions near the outside wall that could be damaged when the drill bit comes through.
- Go outside and use a hole-cutting saw to enlarge the hole so that the cable connector on the back of your electrical box will fit inside.
- Thread a piece of exterior-grade electrical cable from the interior electrical box through the hole in the exterior wall. Be sure the cable is long enough to reach from the interior to the exterior box.
- Inside the house, pull back the insulation sheeting from the electrical cable.
- Attach the ground wires together with a barrel crimp. Be sure to include a short ground wire to connect to your interior outlet.
- Strip the insulation from the black and white wires. Splice white to white and black to black. Also splice short black and white wires to the appropriate connections to power your interior outlet. Secure the connections with wire nuts.
- Reattach the wires to the terminals on your outlet. Attach the white wire to the silver terminal and the black wire to the brass terminal. The ground wire should be attached to the green terminal.
- Reattach the outlet and cover plate.
- Cover the hole in the wall outside with silicone to prevent moisture from entering the house.
- Slide the electrical cable into the box, and position the box as close to the wall as possible while still allowing room to tighten the cable connectors on the back of the box.
- Tighten the cable connectors and mount the box to the wall with screws.
- Connect the electrical cable to the GFCI outlet in the same manner as you connected the interior outlet.
- Install a waterproof gasket onto the electrical box, secure the outlet inside the box and install the cover.
- Turn the power on at the circuit-breaker box and test both the interior and exterior outlets. Be sure to test the GFCI circuit breaker as well.