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Aluminum Wire
| Aluminum wiring was used from about 1965 until about 1975
as an alternative to copper wiring. Most homes built during this time frame have
aluminum wiring.
The outlet in the picture has aluminum wire "backwired" into the outlet - a double negative. |
 |
Aluminum Wiring Concerns:
- Corrosion of the metals can occur in the connections at outlets,
switches and twist-on connectors
- When excessive corrosion occurs it increases the resistance in the
circuit and causes overheating. This overheating can cause fires.
- Aluminum wire overheats more easily than copper.
- According to the US. Consumer Product Safety Commission (CPSC),
homes wired with "old technology" aluminum wiring (manufactured
before 1972) are 55 times more likely to have one or more connections reach
"Fire Hazard Conditions" than is a home wired with copper.
Reducing your Risk
- Risks associated with aluminum wiring at connections can be reduced
by a method of attaching a short copper wire to the existing aluminum wire
with a special crimp on metal sleeve, the COPALUM connector, manufactured by
AMP Incorporated.
- The COPALUM connector is the only method (other than complete
replacement of the aluminum wire with copper) that is approved by the CPSC and
listed with Underwriters Laboratory. It is recognized by many industry
experts as the safest available repair method.
- The COPALUM method must be installed by factory trained
Electricians and may not be available in all locations.
Alternatives
- The COPALUM method is the recommended repair method. Alternatives should only be considered where the COPALUM method is not available.
- Some experts recommend pigtailing with the 3M Scotchlock twist-on
connectors as an alternative. It should be noted that these connectors
are not Underwriters Laboratory (UL) listed, however they have several
features that may make them safer than the "Ideal #65 Twister" UL
listed connector.
- The Ideal #65 Twister connector was listed by UL in 1995 as
acceptable for use as an aluminum to copper connector, however many people
consider it to be inferior to both the COPALUM method and the Scotchlock
twist-on connector. It should be noted that since the Ideal #65 Twister
connector is UL listed, it may be the only connector that will be accepted by
the local building official if the COPALUM method is not available.
- Building officials may accept alternative materials if
documentation of the materials suitability is supplied.
- Changes made by manufacturers in the early 1970's addressed some
concerns with aluminum wire (new technology wire) and devices (marked
CO/ALR) but connections were still made with twist-on connectors and are
still a concern, as a result, this must be considered an incomplete solution.
- To repair a home with aluminum wiring each connection in each device, and the electrical panel
must be repaired.
- Aluminum wire repairs should only be made by a licensed Electrician
using special techniques.
Wire that is typically not a problem
- Aluminum wiring larger than # 10 gauge is still used in homes
today. These larger sizes are generally not a problem.
- Copper clad aluminum wiring has no known history of the types of
problems of aluminum wire.
- Plated copper wire is relatively common in older homes. This wire
looks like aluminum wire, but the copper is visible at cut ends of the wire.
The wire does not need to have these repairs.
References:
- Dr. Jesse Aronstein, "Reducing The Fire Hazard In Aluminum-Wired Homes", May 10, 1996, http://www.inspect-ny.com/aluminum/alreduce.htm
- Aluminum Wiring Hazards web site, http://www.inspect-ny.com/aluminum.htm
- Aluminum Wire Repair, Inc. web site, http://www.alwirerepair.com