Many homes were built using aluminum wiring in the 1970s, and due to implications in numerous house fires, the once common practice is no longer allowed in new installations in most jurisdictions. If your house has aluminum wiring – there is no need to tear down the walls in panic. Aluminum wiring can be just as safe as copper wire, if it has been installed correctly.
Aluminum wiring expands when it heats up, and contracts then it cools. Aluminum reacts differently than copper after many years of warming and cooling cycles. After each cycle aluminum begins to lose some of its tightness. This process is commonly called “cold creep”. Combined this with aluminum’s tendency to oxidize if in contact with certain metals, and these factors can lead to serious problems. When aluminum oxidizes it heats up more to conduct the same amount of electricity, which then causes more oxidation. Due to this cycle, the wires may start to get very hot, melt the fixture that it attached to, and even possibly cause a fire.
If you are considering purchasing a home with aluminum wiring, or have discovered it already, it would be a wise investment to hire a licensed inspector to check over the entire house’s wiring for any possible problems.