Wiring in an attic should be readily visible once you turn on attic lights or use a flashlight. Electricians typically run wiring around the edges of the attic to keep it out of the way. Wiring may also be attached to rafters and ceiling joists, which provide support for cable clamps and mounting brackets. Foam insulation batting or blown-in insulation should never cover wiring. If you store items in your attic, move them away from the attic walls to locate wiring.
Attic wiring requires occasional inspections to ensure it is intact and safe. Trace the wiring throughout the attic while looking for signs of damage. Wiring with frayed plastic insulation may be rubbing against a metal clamp or sharp wooden corner. Installing a foam sheath or simply moving the wiring will keep it from getting worse. Rodents livingin your attic may gnaw at insulated wiring, leaving exposed metal wires or visible tooth marks.
Another reason to trace wiring in the attic is to install new wiring or add a junction box to provide additional outlets or route power to a new area in your home. In this case, you can trace the wiring from the attic to your home's service panel. Locating the source of attic wiring will tell you the voltage of each line, which in turn, tells you which types of outlets you can install.
Before making any alterations to attic wiring, turn off the power to the area. By pulling the correct fuses or tripping breakers, you can eliminate the risk of shocks and electrical burns. If you notice severely damaged wiring during an inspection, turn off the power to that line and replace the entire length of wiring between connectors or hire an electrician to make professional repairs. Improper repairs or unattended exposed wiring can lead to fires.