Aluminum branch circuit wiring
Solid aluminum wiring used for 15- and 20-amp branch circuits in many homes built between roughly 1965 and 1973, associated with an elevated risk of overheating at connections.
What is Aluminum branch circuit wiring?
During a period of high copper prices, solid aluminum conductors were widely used for ordinary 15- and 20-amp branch circuits. Aluminum expands and contracts more than copper and oxidises differently, so terminations at outlets, switches and splices can loosen and overheat over time. The concern is the connection, not the wire itself. Recognised remediation approaches include COPALUM crimps or approved AlumiConn connectors installed by a qualified electrician; simply replacing devices with CO/ALR-rated ones is only a partial measure. Multi-strand aluminum feeders serving a range, dryer or the main service are a different and generally accepted application. Inspectors normally report suspected aluminum branch wiring as a significant finding warranting evaluation by an electrician, since it can also affect insurability.