Aluminum wiring is a major electrical defect and New Jersey home inspectors should inspect for this problematic wire during the electrical inspection of the home. During the years of 1965 and 1973 aluminum single strand wire was sometimes used instead of copper in residential construction. The substitution was primarily driven by soaring costs of copper wiring during this time frame.
Very serious safety issues became apparent with this electrical wiring. The safety issues are caused by the properties of the aluminum in the wiring. Older connections become more of a safety hazard over time. NJ Home Inspectors should describe the safety concerns associated with this type of wiring in the home. Inspectors should have their clients discuss the ramifications of having aluminum single conductor wire in their home with the client’s insurance carrier. Often insurance carriers have concerns with insuring homes when this type of electrical wiring is present.
According to the NJ Home Inspection standards of practice, home inspectors are required to report on the presence of this electrical wiring in a home that they are inspecting. According to the consumer products safety commission homes that have aluminum single conductor wire are 55 times more likely to have an electrical fire then homes without aluminum wire present. Aluminum single strand wire has qualities that make it a poor choice for residential wiring.
Aluminum wire is more fragile than copper wire. Aluminum is not as durable and can break when exposed to bending the wire. Fatigue will cause the aluminum wire to break down, this breaking down will increase the internal resistance of the wire leading to a buildup of heat. Higher electrical resistance means that the wiring has to be a larger diameter of traditional copper electrical wiring. Aluminum wire will also break down in the presence of different metals. This break down is referred to as galvanic corrosion. Also, exposure to oxygen causes the wire to deteriorate on its outer surface. Aluminum wire is much more vulnerable to oxidation then copper wire. Over time this increased oxidation can make electrical connections weak creating fire hazards.
Aluminum wire is softer than copper wire and is more malleable. Take for example when an aluminum wire is screwed to a terminal the wiring will continue to compress over time even though the wire is not being continually tightened. Eventually this defemination will create a loose connection and increase the possibility of electrical arching and fire hazards at these connections.
One of the greatest vulnerabilities of aluminum wire is its tendency for greater thermal expansion and contraction. Aluminum wire expands and contracts with changes in temperature. As current flows though the wire it will expand then contract as the current stops. Over time this expansion and contraction process will cause the connection to become loose, degrade then create fire hazards. Also, electrical current causes the wires to vibrate. This vibration is more pronounced in aluminum wire then copper wire. As time goes by this excessive vibration can cause the connections to become loose and create fire hazards.
How do home inspectors in New Jersey identify the presence of aluminum wire. Aluminum wiring is the color of aluminum and is relatively easy to identify as compared to copper wires. Home inspectors can also look for the word aluminum or the initials “AL” on the wire sheathing. I like to take a long look inside the electrical panel box in order to determine if there are any aluminum wiring circuits in the home that I am inspecting. I also like to remove a few of the junction box covers in the home. This is above NJ standards but it’s a reasonable way to determine if aluminum wire exists. These is no fail-safe method because some unscrupulous sellers have improperly spliced copper to aluminum. I have seen this several times. An electrical contractor can also be bought in to confirm the presence of aluminum wire in the home. NJ Home inspectors should pay particular attention to looking for aluminum wire in homes that were constructed between 1965 to 1973.
Aluminum wiring should be evaluated by a qualified electrician who is experienced in evaluating and correcting aluminum wiring problems. Not all licensed electricians are properly trained to deal with defective aluminum wiring. The CPSC recommends the following two methods for correction for aluminum wiring:
What can be done to correct this significant safety hazard? The most effective way to make a home safe is to re-wire the house. Re-wiring the home is very expensive and is often not very practical. Copalum connectors can also be used. In this method, a length of copper wire is attached to the aluminum wire with a special metal sleeve with a crimping tool. This connection can only be applied with the required crimping tool. Although effective they are also very expensive.
There are also some other methods of aluminum wire correction. however, these methods are not approved by the consumer products safety commission. Pig tailing is a method of correction where a short piece of copper wire is attached to the aluminum wire with a twist connector wire nut (usually purple in color). The copper wire is then attached to the electrical outlet, switch or terminal. Some insurance companies will accept pig tailing and others will not. Pig tailing will increase the number of electrical connections in a home. The higher number of connections the greater chance of connections loosening and becoming problematic. Also, the client can replace certain failure prone types of devices and others with more compatible with aluminum wire (not recommended)
Home Inspectors in NJ should properly inspect homes for the presence aluminum wiring in homes they are inspecting. If found it is the responsibility of the home inspector to properly educate their clients on the potential hazards of aluminum wire and the possible corrections that are available to them to correct the issue.
John Martino
LookSmart Home Inspections
NJ Home Inspectors Lic # 24GI00058700
Board Certified Master Home Inspector
American Society of Home Inspectors (ACI) #244472
International Association of Certified Home Inspectors (CPI) # 200090933
NJ Radon Lic# MET 11963
Commercial Pesticide Lic. (Termite Inspection License) # 27811B
Certified Mold Inspector
5 Preston Ave
East Hanover, NJ 07936
973 407-9621