A barn is more functional with lights and electrical receptacles.
ROMEX® and MC cable are both good choices for wiring a barn. ROMEX® originated as a brand name that has become generic. It is a cable that contains two to four wires individually covered with plastic insulation and wrapped with paper. The wrapped wires are encased in non-metallic sheathing, usually plastic. ROMEX®, sometimes referred to as NM cable, is suited for use inside buildings. MC cable has two to four plastic-coated wires encased in metallic clad sheathing instead of plastic. It is suited for underground installations because the metal clad sheathing keeps moisture from the wire.
Instructions
1. Install octagon outlet boxes in the barn where you want lights. Attach switch boxes to the walls for light switch and receptacle installation. Ensure that the boxes have ROMEX® clamps.
2. Mount a disconnect switch on the wall where the electrical service will enter the barn. Run one cable from the disconnect switch to connect all outlet boxes together and a second cable to connect receptacle boxes together. Attach the cable to walls and ceiling between the boxes with ROMEX® staples.
3. Run a separate piece of wire from one of the outlet boxes to the switch box.
4. Leave about 1 foot of cable hanging out of each box. Tighten the ROMEX® clamps and peel the sheathing from each cable end.
5. In the outlet boxes, connect all the black wires together with wire nuts and to the brass screw on keyless porcelain ceiling sockets. In one outlet box, connect the white wire coming from the switch box to the lighter colored screw on the light socket and connect the remaining white wires together. In the other outlet boxes, connect all white wires together and to the light sockets. Use short pieces of wire to connect the light sockets to the other wires. Connect all green wires together.
6. Install the switch and receptacles by attaching black wires to the brass screws and white wires to the lighter colored screws. Attach the switch and receptacles to the boxes with the attached screws and cover with metal plates.
