Aluminum building wire is considered a safe, effective solution for today’s commercial and residential buildings. Its reputation for high performance at a low price point is well deserved. However, this wasn’t always the case.
Developed in response to the copper shortage following WWII, aluminum building wire had a rocky start right out of the gate. With growing demands for new veteran housing and a booming commercial sector, the subsequent need for building wire was dire. Enter aluminum — a readily available, yet untested alternative to hard-to-find copper wire. What followed was a series of events that tarnished aluminum wire’s image for decades to come.
Here, we will review those events, as well as the solutions put in place that have made it the viable, cost-effective product it was originally intended to be. Keep reading for the whole story.
An Untested Product with Unfortunate Consequences
The first aluminum building wire rushed to market in the 1950s was constructed from the same electrical-grade aluminum used in transmission lines. Unfortunately, the high tensile strength and highly conductive properties of this type of aluminum results in very low material elongation and other characteristics that are undesirable in a building wire conductor.
At the same time, due to the ongoing copper shortage, the brass screws in electrical devices were replaced with steel screws. Due to time constraints, this switch was made without proper testing or listing. Unfortunately, electrical device manufacturers were unaware that a compatibility issue existed between steel screws and aluminum wire. In fact, the characteristics of each of the materials was such that under the heating and cooling experienced during operation of a device, the wire terminations would often loosen. This caused high-resistance connections and heating. Ultimately, these poor connections resulted in residential fires. And the rest is history.
A New Start with a New Aluminum
In 1968, Southwire®
Company led the way in the development of new aluminum building wire technology with the advent of Triple E aluminum (now trade-named AlumaFlex™). Starting with a clean slate, metallurgists developed an aluminum alloy that possessed all the characteristics considered desirable in a building wire. Finally, for the first time aluminum building wire was being made from an appropriate alloy instead of a poor fitting hand-me-down from another industry.
This new aluminum alloy, developed and patented by Southwire, bridged the gap in the key metal characteristics between copper and aluminum. Characteristics such as elongation, thermal stability, compressive creep and flexibility were much closer to those of copper. Soon others in the industry recognized the benefits, and in 1985 the National Electrical Code®
required 8000 series aluminum alloy in aluminum building wire applications. In addition to utilizing a new aluminum alloy, aluminum building wire and devices were being tested and listed for compatibility. The use of compatible materials, proper testing and listing resulted in a reliable aluminum electrical wiring method.
A Safe and Reliable System
Aluminum building wire is something few people in the residential and commercial electrical industry don’t have a passionate opinion about. More often than not, you will find their opinions are based on facts that are more than 50 years old. The plain fact of the matter is that aluminum building wire, through the efforts of manufacturers like Southwire®
and organizations such and the NEC®
, is a proven safe and reliable system.
Additionally, aluminum building wire has some advantages over copper. For example, it’s much lighter and more cost-effective. This can result in easier installations, fewer injuries, more conductivity, and higher margins. Colleagues of yours who have already embraced aluminum building wire and are reaping the benefits, may very well be hoping you walk away from this article clinging tight to your misconceptions since they could be bidding their next job against you
. We highly recommend you take a closer look first.