How to Upgrade the Electrical Wiring in a House

Replace the Panel

• 1

  Draw a plan of your new wiring so you know how much cable to buy. If you need more circuits for more lights and receptacles, draw them out so you can calculate how many new devices you need, where they'll go and how much extra cable you'll need.

• 2

  Call the power company and ask for a technician to disconnect your meter. In many communities, the meter is the property of the power company, and only its representative is authorized to disconnect it.

• 3

  Open your old panel when the power is off, and disconnect the main leads and all the circuit wires. If you have an old circuit breaker panel, pull out the breakers so you can disconnect the wires attached to them. If you have a fuse box, you don't need to remove the fuses. Pull the wires out of the panel and unbolt the panel from the wall with a wrench. Replace it by bolting a new one large enough to handle your electrical demand in its place.

• 4

  Feed the transmission leads into the top of the new panel and connect them to the lugs on the brass bus bars with a screwdriver. The leads are red and black, and you can connect either of them to either of the bars.

• 5

  Ground the panel by driving a ground stake 8 feet into the earth as close to the panel as possible. Run a length of 10-gauge copper ground wire between the stake and the panel. Connect one end to the stake with a grounding clamp and one end to the ground bus on the panel. The panel is now ready for connections.

Replace the Wiring

• 6

  Disconnect the old circuit cables from the devices to which they are attached and pull out as many of them as you can. Some may be inaccessible because they are stapled to framing that is behind walls. If you're not remodeling and don't want to remove the wall coverings, cut them with wire cutters and leave the stapled sections where they are until such time as you have occasion to open the walls.

• 7

  Remove all old ungrounded receptacles, switches and light fixtures so you can replace them with grounded ones if you are upgrading from an ungrounded two-wire system. Replace outlets in the bathroom, kitchen, basement and outdoors with Ground Fault Interrupting (GFI) receptacles. Install electric boxes for all the new devices you plan to add.

• 8

  Run new 12- or 14-gauge electrical cable from the panel to all the devices according to the plan you made. If your panel is in the basement, run the cables along the floor joists, stapling them as you go, and pass them vertically upward through holes in the floor into the walls where they are needed. You can also feed the cables from the panel into the attic, where you can run them laterally and drop them into walls as needed. Connect the wires to all the devices.

• 9

  Feed all the cables into the panel through knock-out holes in the side or bottom. Screw a knock-out clamp onto each hole, feed in as many cables as will fit, and tighten the clamp. Strip the ends of all the cables with a utility knife so you can make connections.

• 10

  Feed the white wire from each cable into a slot on the silver bus and the ground cable into a slot on the ground bus, tightening the screw on each slot with a screwdriver.

• 11

  Connect the black wire from each cable to a circuit breaker. The breaker rating should correspond to the expected current draw for each circuit. Snap each breaker onto the front of the panel and label the circuit on the panel door or cover. When the panel wiring is complete, reconnect the meter and turn on the main breaker.