Aluminum Wiring In 1970s Homes

Certain housing developments in Lopatcong, New Jersey built in the early 1970s used single strand aluminum building wires. This wiring is deemed unsafe by today's standards. A study by the Consumer Product Safety Commission found that homes with aluminum wiring were 55 times more likely to have an outlet that reached "fire hazard conditions." This aluminum wiring was used during copper shortages for 15- and 20-amp branch circuits throughout these houses. At the time, wiring devices (outlets, switches, and breakers) weren't designed for the different thermal expansion of aluminum wiring. This alloy was also brittle and prone to breaking off.

Aluminum wiring is still widely used today. It is likely that the wiring from the power company to your home is aluminum, and if you have an electric range oven, they are often fed with stranded aluminum cable. The difference is modern aluminum wire is made out of AA-8000 series alloys that behave more like copper wire.

So, when selling or buying a home from the mid 1960s to the mid 1970s, what is to be done so that we can be confident in the home's electrical system?

•  The safest thing to do is to completely rewire the house with modern copper NM cable. This can be very expensive and involve opening up walls and ceilings to replace wiring entirely.

• The next best thing is to "pigtail" every outlet, switch and light fixture. Splicing the aluminum wire to copper wire using special connectors that are rated for the different thermal changes between the copper and the aluminum wires. We can use King Innovation Alumni Conn or Ideal Twister connectors. The Consumer Product Safety Commission still considers the Ideal Twister connectors to be a temporary solution, although they have been UL listed since 1995.

• The third option is to replace all devices with CO/ALR Devices. This approach still leaves brittle aluminum wiring on device terminals, and it doesn't address light fixtures which will need to be pigtailed.

What not to do: Leave the aluminum wiring alone without mitigating the hazard. Call McCaffrey Electrical Contracting today (908) 818-0460 or email dan@mccaffreyelectricnj.com for more information or a quote to mitigate aluminum wiring.