Potential Dangers of Aluminum Wiring
A recent survey commissioned by the US Consumer Product Safety Commission found that houses built before 1972 are still using aluminum in their branch circuit wiring. This makes them fifty-five times more at risk of Fire Hazard Conditions than homes using copper wiring.
Even more worrying is that the survey, carried out by the Franklin Research Institute, only covers wiring connected at outlets, without looking at further connections and splices within the circuit.
Aluminum wire connections deteriorate over time. This leads to a build-up of resistance to the flow of current. The result is overheating to levels that can present a very real danger of fire.
Why Use Aluminum?
The use of aluminum wire in older houses can be traced back to a copper shortage in the 60s. Builders turned to aluminum as an alternative in residential electrical wiring systems.
This explains why most houses built pre-1965 don’t have aluminum wiring, and why installations carried out between 1965 and 1975 do. In some cases, the main house will have copper wiring, but later additions will contain wiring with aluminum.
Signs of Trouble
There are a few tell-tale signs that can herald trouble with the electrical system. Flickering lights, switch faceplates that feel too hot to touch, circuits that simply stop working, or a burning plastic smell near switches and outlets, are the most common.
How to Check if Your Wiring is Aluminum
It’s not always easy to distinguish between copper and aluminum wiring because they are both encased in the plastic sheathing. Ideally, you’ll be able to see “Al” or “Aluminum” embossed on the cable jacket every couple of meters along the length. You may also find clearly visible electrical cables in unfinished basements, or perhaps in the garage. If you’re still not sure whether your wiring is aluminum or copper, call in an electrician to make a professional assessment.
Fixing the Problem
Once you’ve established your home does have aluminum wiring, the CPSC recommends you take action to reduce the risk of overheating. While the most effective solution is to replace all aluminum wiring with copper, this is not always practical or affordable.
Replacing the aluminum with copper will do away with the main cause of the fire hazard, but the cost and the practicalities of the task will depend on the architectural style of your home and how many unfinished spaces, such as attics and cellar spaces, it contains.
A less complicated and more affordable solution is often called ‘pig-tailing.’ It involves attaching short strips of copper to the ends of the aluminum wires with special COPALUM connectors. The connectors are installed using a metal sleeve and crimping tool, essentially making a cold weld. The method is considered a safe and permanent solution, as long as every connection in the home is included. This means all outlets, switches, appliances, including dimmers.
The COPALUM solution has been thoroughly researched and meets the CPSC’s safety standards. It’s been common practice for over twenty-five years and is a lot cheaper option than a complete rewiring. Plus, it’s simple to install in a home that’s occupied and furnished.
While there are other crimp connectors available on the market, they may not meet the required safety standards and are best avoided. Remember that all modifications to pre-installed electrical wiring must be carried out by a qualified electrician and should be checked in accordance with local regulations.
It’s not always easy to detect when aluminum wiring is about to fail. Some reports of connections and splices overheating have shown no prior warning of the danger. If you suspect a problem with your aluminum wiring, you should not try to deal with it yourself. The best thing is to ALWAYS call in a qualified electrician.