DO-IT-YOURSELF : Surface Wiring Works in Right Places

Much of the dread of making an electrical upgrade is based on the need for cutting into finished walls and ceilings. Fishing wire through closed spaces is always a gamble as hidden structural components can foil the entire effort. Then, of course, there’s the problem of wiring along brick or masonry walls.

One solution to these problems is decorative surface wiring. Although it’s not the most desirable option under ideal conditions, the system can be a real problem solver in the right places.

Surface wiring is not a new concept. We’ve seen it in old schools and commercial buildings. The difference today is that modern surface wiring components are not only attractive, but also come in a range of colors and profiles. Some are also made of plastic, which eliminates the need for redundant grounding.

A typical installation of one new receptacle and a switched ceiling light requires enough channel to reach the new box locations, three box extensions, a T-connector to branch to the switch, an inside-corner connector to carry the channel across the ceiling and a round ceiling fixture box. You also need a few accessory packets that include an assortment of wire clips, track connectors, screws and plastic anchors.

Several electrical code requirements will rule your installation. To determine whether your circuit has enough capacity for the new components, assign 1.5 amps to each existing outlet. At this rate, a 15-amp circuit will handle 10 outlets, and a 20-amp circuit will handle 13 outlets. Shut off your circuit and use a lamp to verify which outlets are without power. Then add up the number of dead outlets to determine how many new fixtures or boxes can be added.

Each receptacle and fixture also needs to be grounded, as does any metallic box you use as a starting point. All ground connections should be made with insulated wire, and all wires should be the same size as those used in the existing circuit.

Also, check with local codes for the number of wires allowed per box. You are allowed to count all ground wires as one and each device as one. Generally speaking, you are allowed six wires per track and box.

Basic surface wiring installation highlights begin with unscrewing the receptacle from the power-source box. Then slip on the new base plate. Cut the surface wiring base channel to length, and bore holes through the channel on 18-inch centers. Level the channel and mark the hole locations on the wall.

Secure the channel along with necessary T- and L-connectors with drywall anchors. Use an awl to punch anchor holes through the base plates and secure with drywall anchors and screws.

Lay the wires into the channel and use wire clips to hold them in place. Use wires of the same size as the original circuit. Conceal the wiring by installing the outer trim channels that snap in place over the base channels.