Copper Clad Aluminum a short lived era.
A relic of the mid 70’s wiring in residential applications was the Copper Clad Aluminum (CCA) Wiring.
Due to the copper shortage of the mid 1960’s and early 70’s aluminum became an option as a cost effective materials for residential branch wiring. The issue was that these early aluminum alloys had a hidden problem.
The aluminum used suffered what was called thermal creep and galvanic corrosion. The compounding issue was many of the devices such as receptacles were not rated for aluminum connections.
By 1973 an alloy of aluminum was introduced known as AA-8000 series aluminum
alloy. This was a fully annealed, strong and flexible conductor material and could be used in standard installations to devices as long as those devices were CO/AL rated.
But during the time before the full development of a new aluminum alloy entered another cost effected alternative, Copper Clad Aluminum (CCA). CCA was known as a Bimetal and not an alloy. A bimetal is a physical bonding of two separate distinct metals. This allowed the conductor to maintain the best properties of each of the metal involved which was copper and aluminum without the issues suffered from the aluminum- creep and corrosion.
Aluminum Building Wire Installation and Terminations (IAEI article from 2006)
https://iaeimagazine.org/magazine/2006/01/16/aluminum-building-wire-installation-and-terminations/
By the later 70’s and with new supplies of copper available CCA had run it course.
If you find any errors or have additional information that would expand on any code, building standards or manufacturer requirements please let me know.
NCW Home Inspections, LLC is a Licensed Washington State Home Inspection service located in Wenatchee Washington serving Chelan County, Douglas County, Kittitas County, Okanogan County and Grant County Washington and the cities of Wenatchee, Leavenworth, Cashmere, Oroville, Cle Elum, East Wenatchee, Quincy and many more…
Your Wenatchee and Chelan Professional Real Estate, Home and Structural Pest Inspection Service
Coordinator & Instructor- Fundamentals of Home Inspection- Bellingham Technical College
Former WA Home Inspector Advisory Licensing Board
www.ncwhomeinspections.com 509-670-9572
You can follow me on Facebook, Twitter, Google+ and on my website Blog.
