Ideally, you want to be able to take your home’s electrical system for granted. It should power your lights and appliances reliably, safely and invisibly.
But it’s important to notice warning signs that an experienced professional should examine a system. Our researchers compiled these indicators, based on interviews with highly rated electricians:
Also, make sure you know what kind of wiring winds through your home. Copper is the ideal material. Pre-1940s knob-and-tube wiring and 1960s-era aluminum wiring are associated with greater fire risk.
Knob-and-tube systems feature porcelain knobs that anchor wires to studs and floor joists and insulated tubes that carry wires through walls and other obstructions. Such systems have separate hot and neutral wires that run parallel to each other and dissipate heat into the air. They can become a fire hazard if overburdened, improperly retrofitted or come in contact with insulation.
Problems with aluminum wire generally occur at connections, where exposed aluminum wire may rust, resisting current flow and generating heat. Aluminum also expands and contracts in response to load and temperature changes differently than copper or other materials, so connections between aluminum and other metals can lead to problems that reduce conduction.
If you live in an older home and aren’t certain of its wiring type or safety status, schedule an inspection by a licensed, experienced electrician.
In the case of knob-and-tube systems, you may be able to upgrade one room at a time, especially during a remodeling. With aluminum systems, an electrician may recommend total replacement with copper, or may replace connection points where aluminum wire is exposed to other metal types or air.
No matter what kind of wiring you have, experts recommend these do-it-yourself safety steps: