Millions of American homes contain aluminum wiring, and there is a chance that some of these houses will someday experience electrically-caused fires. Aluminum wiring isn't always dangerous, but it can pose a real hazard if the conditions are wrong. Below is more information about aluminum wiring, including what you should do if you suspect your home contains it.
Why Aluminum Wiring Was Popular
Copper is one of the best conductors of electricity and has always been the metal-of-choice of wiring manufacturers as a result. However, dramatic copper cost increases in the 1960s and 1970s forced manufacturers to raise the price of finished electrical wiring. This, in turn, placed a burden on homebuilders seeking to keep construction costs low.
When an alternative was sought, aluminum managed to make its way to the forefront due to its excellent conduction characteristics. Also, aluminum cost much less than copper, which also made it an attractive option. Wiring manufacturers transitioned to aluminum, and huge numbers of homes were built with aluminum wire as its primary electrical "backbone".
What Is Wrong with Aluminum Wiring
Several secondary characteristics make aluminum wiring a risky option in terms of fire potential. These potential problems include the following issues.
Increased Expansion Potential
One reason why aluminum wiring poses a fire hazard is that it will expand to a greater degree than copper. Heat causes all metals to expand, but aluminum is more affected in this regard than most other metals. As a result, the creation of heat due to electrical conduction causes aluminum wiring to literally grow in length; when you remove the electric current, aluminum wire cools and contracts.
The cycle of expansion and contraction can interfere with the joints between aluminum wire and connectors. This "push-pull" effect can loosen screws, pull wires out of backstabbed connections, untwist wire nuts and even break wires. While copper also expands, it does so to a much less degree and causes far less stress on connectors.
Loose or broken connections are hazardous because of the increased chance of arcing and short-circuiting. Arcs and short circuits create sparks and also may allow current to flow through other locations, which ultimately may cause fires.
More Vulnerable to Being Damaged
Aluminum wiring is also more vulnerable to being damaged than copper wiring. Aluminum is a soft metal, even more so than copper, and it can be easily nicked and cut. These nicks and cuts interfere with the orderly flow of electrical current and create pockets of electrical resistance. Resistance from an electrical perspective generates heat, which in turn can cause a fire.
Oxidation and Conductivity Problems
The technical term for corrosion, oxidation, describes what happens when oxygen combines with metal. Rust is an oxidation byproduct of iron and steel, for example. In the case of copper, the oxidation byproduct (copper oxide) is green-colored and is conductive like its parent metal.
However, aluminum oxide, the oxidation byproduct of aluminum, does not conduct electricity. This poses a problem due to the potential for interfering with electrical current flow and possibly causing a fire. Also, since aluminum oxide is a strong thermal conductor, the heat generated by resistance can readily travel through the oxide and rapidly develop into a fire.
What Should You Do In Response to Aluminum Wiring
If you suspect you have aluminum wiring in your home, the first step is to contact a qualified electrician for a wiring inspection. They will be able to evaluate your electrical system and determine if any aluminum wiring has been used inside your home.
Should aluminum wiring be discovered, they will also provide a recommendation as to what should be done to correct any potential problems. For example, the electrician will decide whether or not all aluminum wire should be completely removed or if only wire attached to connectors should be replaced.
If you live in the Baton Rouge area, be sure to contact Nicotri Electric, Inc. for help. Their professionals are able to provide you with assistance with all of your home's electrical needs.