Our View of Aluminum Wiring

Based on our research and inspection experience, the use of aluminum wire should not be a reason to avoid buying a house. There are, however, some cautions about aluminum wire that should be discussed with potential buyers. Not only do our inspectors examine the accessible electrical system per ASHI® (American Society of Home Inspectors) standards, we present this information in a manner that helps clients keep the issue in perspective.

Brief History
Builders began using aluminum wire in around 1965, when the price of copper wire skyrocketed. A considerable number of homes have aluminum wiring -- in fact, in most areas of the United States the use of aluminum wire is still code permitted.

Many studies have shown that electrical problems are more likely to occur with aluminum wire than with copper. However, most concerns are restricted to single strand aluminum wire used in branch circuits not the stranded heavier gauge wire used for service entrance and large appliances. Single stranded wire tends to work loose at the screw terminals causing overheating, malfunctions and occasional fire. Correcting these problems led to changes in installation methods around 1973.

New Technology
Homes constructed with aluminum wire since 1973, have "new technology" wiring that comply with electrical codes requiring UL listed circuit breakers, receptacles, switches, and wire nuts ( i.e., aluminum compatibility labeling: CO-ALR or CO-AL). Installed properly, these devices keep the connections tight and should greatly reduce any potential problems. If an outlet or switch ever needs to be replaced, replacement devices should be labeled "CO-ALR".

Old Technology
Unless upgraded, homes built between 1965 and 1973, have "old technology" aluminum wiring. There are few documented cases of house fires caused by aluminum wiring - with the majority of problems involving mobile homes and recreation vehicles. "Old technology" aluminum wiring will usually perform satisfactory if properly installed. There are no code requirements to make improvements and typically insurance companies will not refuse to cover a home with aluminum wiring. However, homeowners should watch for warning signs and consider some form of upgrade from an electrical specialist.

Homeowner suggestions include:
With every inspection we provide 12 months of our Extended Advice program so your clients always have a direct source for accurate information about their homes. For aluminum wire, we recommend the following:

• Be aware of warning signs: excessive light dimming, arcing at switches, warm cover-plates at switches or outlets, strange odors, burnt wires or corrosion on electrical connections, or faulty outlets or circuits.
• Periodically check the connections at outlets and switches to make sure wires are tight and there are no hot spots. Hot or warm outlets and switches indicate a need for repair.
• If you wish to be proactive or have a concern, upgrade old technology by replacing switchesand outlets with the labeled CO-ALR devices.
  

We’re working to be your expert -- we’re working to earn your business.
Minnesota Home Inspectors