How to Join Outdoor Electric Wiring

Joining outdoor wires has special considerations.

Outdoor electrical wiring provides power for exterior lights, outlets and sheds. Special outdoor-rated wire is used to prevent moisture from touching the conductors. To protect electrical connections from the same environment and people from being electrocuted, all wire splices must be made in an outdoor-rated junction box. These boxes should be accessible for future inspection and repair. Making a safe electrical connection is a little more than joining the like-colored wires.

Things You'll Need

• Noncontact voltage detector
• Wire cutters
• Wire strippers
• Outdoor junction box
• Wire nuts
• Screwdriver

Instructions

1. Turn off the power to the circuit you are working on at the home's distribution panel. Confirm the power is off by touching a noncontact voltage detector to the wire's insulation.

2. Strip 3/8 inches of insulation off both of the wire's three conductors with wire strippers.

3. Push each of the wires through the two separate rubber grommets on the side of the exterior-rated junction box. Pull 6 inches of wire into the box and secure the wires to the box by tightening down the screws for the wire compression mechanism.

4. Twist together the like-colored wires with pliers and install a wire nut on top of each of the three connections.

5. Fold the wires neatly into the box and mount the cover with the four screws provided.

6. Fasten the junction box to a solid object like an exterior wall or wood joist on a deck. The junction box should be in a location to minimize the chances of mechanical damage and contact with the ground.

Tips & Warnings

• Electricity can be very dangerous because it only takes a small amount to hurt you, and it is invisible. Double check the power is off before touching the wires.

References

• Dully: How to Install Outdoor Wiring
• Ask The Electrician: Electrical Junction Box Splice