How to Reduce the Risk of Aluminum Wiring
Fires InspectAPedia® -
How to reduce the risks associated with aluminum electrical wiring
Aluminum wire repair method details and aluminum wire repair products are described here
Aluminum to copper pigtailing & aluminum to aluminum wire splices are here
This website answers nearly all questions about aluminum wiring inspection, hazards, repairs
Our site offers impartial, unbiased advice without conflicts of interest.
We will block advertisements which we discover or readers inform us are associated with bad business practices,
false-advertising, or junk science. Our contact info is at
InspectAPedia.com/appointment.htm.
This article summarizes the immediate safety steps needed in a building where solid conductor aluminum electrical wiring is installed. Here we describe the acceptable methods to repair aluminum wiring, including which aluminum wire connectors to use for safest results.
HOW TO REDUCE THE RISK of Fire and Electrical Circuit Connector Overheating in Buildings with Aluminum Electrical Wiring
Immediate Actions for Safety of Aluminum Wiring
See if you have aluminum wiring (solid conductor branch circuit) installed in your home. Aluminum wiring identification tips are
provided at How to Recognize Aluminum Wiring
Look for signs of aluminum wiring failure, such as flickering lights, turn off the circuit involved and call a licensed electrician. See U.S. CPSC 516 (linked-to below) for other trouble signs.
Install smoke detectors at locations recommended by your local building officials or fire department. Sample smoke detector locations are also provided on instructions that come with the smoke detector.
How to Repair Aluminum Electrical Wiring to Reduce the Hazards
Once the initial steps above have been addressed here are the choices for safe repair of aluminum wiring:
Re-wire the Building replacing all aluminum branch circuit wiring with copper, as a "best repair method" for aluminum wiring, OR as a
next-best aluminum wiring repair method
COPALUM Copper-to-Aluminum Pigtailing Use the special AMP (now TYCO) COPALUM connector and special tool to
connect short copper wires to every aluminum wire end in the Building, reconnecting the copper to the
various devices (outlets, switches, lights) and splices. This "copper pigtailing" procedure is performed by an electrician trained
and licensed by AMP or TYCO to use this COPALUM procedure.
The TYCO COPALUM connector method is described
is described at PIGTAILING USING AMP "COPALUM" CONNECTORS.
Typically this approach costs about half that of completely re-wiring a home with copper.
COPALUM Aluminum Wire Connector Availability discusses how
to get these aluminum wire connectors, and at MAKING SPACE FOR ALUMINUM WIRE CONNECTORS we discuss options for fitting the COPALUM connector and pigtail wires into electrical boxes where space is tight.
Currently only these two remedies above have been formally recommended by the CPSC. Other aluminum wiring repair connector products
have been sold by various manufacturers, some with good performance and some unacceptable. Descriptions are below. Emergency temporary
repairs necessary to keep an essential circuit in service might be possible following other procedures described by the CPSC or by industry experts.
AlumiConn TMaluminum to copper lug connectors[New in 2006, U.L. Listed, 2007 completed independent testing]
available from King Innovation. Results of independent
testing indicate that this product "... is predicted to have a high probability of failure-free long-term safe performance,
PROVIDED THAT THE SETSCREWS ARE CAREFULLY TIGHTENED TO THE MANUFACTURER'S RECOMMENDATION".
Reference: details of the study and recommendations are on page #6 (the 9th page in the .pdf file) in Dr. J.A. Aronstein's .pdf document version of
"Reducing the Fire Hazards in Aluminum Wired Homes" May 21, 2007.
The test results are completed and will be published in September 2007.
(100 connectors cost $285. Lower prices for larger quantities.) At MAKING SPACE FOR ALUMINUM WIRE CONNECTORS we discuss options for fitting the AlumiConn™ connector and pigtail wires into electrical boxes where space is tight.
Technical note on binding and poor wire connections in aluminum terminal blocks:
In larger-sized electrical wire connector applications such as electrical panel buses (not this product),
we have seen aluminum-block connection
failures occur when the steel screw bound in the aluminum block,
appearing to be a tight connection before proper contact with the wire has been made.
Mr. King informs us that they have addressed this concern by plating the screws in nickel and plating the lug block in tin,
thus eliminating the galling found in other lugs. Also there is a very small gap at the back of the
wire terminal block where the installer can see the wire (coated in sealant) coming through. This
provides visual confirmation that the wires came all the way through.
Finally, King always recommends that installers to check the connection security by giving a quick tug on the
wires to make sure they are tight. This UL-listed connector has not been recommended, nor recommended against, by the US CPSC.
How to Repair Aluminum-to-Aluminum Wire Connections in Buildings
Aluminum to aluminum wire splices also need to be repaired in an aluminum-wired home. The various "copper pigtailing" methods
discussed in articles on aluminum wire repairs (at aluminum-wired devices such as electrical receptacles, switches, and lights)
are not the best approach when repairing aluminum-to-aluminum wire splices such as at a
junction box in a building (where several aluminum-wire circuits or wires are joined together).
[DF note: For the aluminum wire to aluminum wire connector case, use of a splicing connector whose manufacturer specifies that the connector must be used with a combination of copper and aluminum wires together makes little sense.
Our photograph at above left shows aluminum wire spliced to aluminum wire at a connection which had not overheated when we took this photo. The photograph at above right shows severe overheating and burn-up of an aluminum to copper splice made using a conventional twist-on connector. ]
For the small aluminum wire sizes such as found in building branch circuit wiring for lighting and receptacles, the AlumiConnTM is probably the best choice if the COPALUM connectors and special crimping tool are not readily available.
For larger aluminum wire sizes sizes (stranded aluminum wiring such as found at air conditioning compressor circuits, electric
range circuits, clothes dryer circuits and other high-amp devices), any of the (UL listed for Aluminum) setscrew type connectors
in combination with the inhibitor/abrasion installation technique should suffice.
Since we've seen frequent field reports of overheating at multi-strand high-amp aluminum wired devices such as air conditioning compressors, it is important
to address these cases by proper repair methods. [Note: some air conditioning equipment manufacturers currently recommend use of only
copper wiring to feed their equipment - DJF June 2007]
Other Approaches to the Repair of Aluminum Electrical Wiring
Scotchlok 3M Special Method [- superceded by new alternate repair as of June 2007 -]: this ""Scotchlok 3M Special Method was previously recommended as independent tests showed that it performed acceptably.
While this repair method has been superceded by new alternate repair as of June 2007, we have kept this description available to aid home buyers, electricians and home inspectors
who may discover or need to be able to recognize this aluminum wire repair method if it was previously used in the building. A summary of this method is at
"Scotchlok 3M connector" and details of this method are
at Aluminum Wire alternative repair: Special Aluminum Wire Repair Method
Other methods - not recommended: Warnings regarding other "repair" methods which are not recommended
are discussed at OTHER REPAIR PRODUCTS, such as the
Ideal 65 purple "Twister" aluminum wire splice connector shown in the photo at left (12 connectors cost $49. to $79.)
Other methods - also not recommended: include attempts to repair aluminum wiring using
receptacles and outlets marked "COALR" (even if these worked, which has not been
demonstrated, what about all of the other electrical connections and splices in the building?). COALR and CU/AL devices
as a "repair" for aluminum wiring is discussed at OTHER REPAIR PRODUCTS.
Reducing the Fire Hazards in Aluminum-Wired Homes - 2007 Update, [large .pdf document], Jess Aronstein, Ph.D., 21 May 2007. This document answers most technical questions about the hazards and remedies of aluminum electrical wiring and includes
a report on independent test results of alternative products and methods for repairing aluminum wiring.
Critique, contributions wanted: Contact Us to suggest corrections or additions to articles at this website, and if you wish, to receive online listing and credit as a contributor. Particular thanks are due to the many experts and also consumers who read and critique technical articles at InspectAPedia.com.
Additional technical contributors & reference sources for this article are listed below.
Use links just below or at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.
Dr. Jess Aronstein, protune@aol.com is a research consultant and an electrical engineer in Poughkeepsie, NY. Dr. Aronstein provides forensic engineering services and independent laboratory testing for various agencies. Dr. Aronstein has published widely on and has designed and conducted tests on aluminum wiring failures, Federal Pacific Stab-Lok electrical equipment, and numerous electrical products and hazards. See Aluminum Wiring Bibliography and see FPE HAZARD ARTICLES, STUDIES for examples.
"The Influence of Corrosion Inhibitor and Surface Abrasion on the Failure of Aluminum-Wired Twist-on Connections",
Aronstein, J.; Campbell, W.,
Components, Hybrids, and Manufacturing Technology, IEEE Transactions on
Volume 7, Issue 1, Mar 1984 Page(s): 20 - 24
WANTED: Aluminum Wiring Field Reports, Photographs, Samples, & Failure Cases & Data for ongoing study on frequency and severity of occurrence of problems.
If you have experienced any problem, or symptom of possible problem with aluminum electrical wiring, or have repaired or replaced it, please contact Daniel Friedman. All information is confidential.
Study results will be provided to the U.S. Consumer Product
Safety Commission and to the electrical industry. Real life aluminum wiring field failure reports can be seen at Aluminum Wiring Failures in Residential Properties: Field Reports & Pictures.
Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair
Our recommended books about building design, inspection, and repair, and about indoor environment testing, diagnosis, and cleanup are at the InspectAPedia Bookstore.
Recommended books on electrical inspection, electrical wiring, electrical problem diagnosis, and electrical repair can be found in the Electrical Books section of the InspectAPedia Bookstore. (courtesy of Amazon.com)
How to Reduce the Risk in Buildings with Aluminum Electrical Wiring - Overview of Acceptable Repair Practices (in the document you are presently viewing)
Aluminum Electrical Repair Method Details - "How to" details, how to identify, COPALUM repair, alternative repairs, history, products, research, source of special AMP TYCO COPALUM connectors & COPALUM Electricians (in the document you are presently viewing)
COPALUM Electricians: Sources of TYCO COPALUM -Certified/Trained Aluminum Wire Repair Services (in the document you are presently viewing)
05/21/2007 Reducing the Fire Hazards in Aluminum-Wired Homes, [.pdf document], Jess Aronstein, Ph.D., 21 May 2007. This document answers most technical questions about the hazards and remedies of aluminum electrical wiring and includes
a report on independent test results of alternative products and methods for repairing aluminum wiring. Some of the sections of this very thorough document are listed below:
02/09/2006Reducing the Fire Hazards in Aluminum-Wired Homes, Jess Aronstein, Ph.D., This older version of the above document also answers most technical questions about the hazards and remedies of aluminum electrical wiring
but lacks latest repair product testing such as the AlumiConn connector discussed above. Some of the sections of this very thorough document are listed below:
[UPDATED-DF 03/08/2003, Edits-df 02/09/2006]
Pigtailing using COPALUM - CPSC recommended,
Pigtailing using Scotchlok 3M - superceded by new alternate repair as of June 2007 - a tested, useable aluminum wiring connector method, with a link to step-by-step "how to" photos,
Pigtailing using Ideal 65 - NOT RECOMMENDED, aluminum wiring failures research, field and lab experience, expert sources.
Circuit Breaker, a bad one fails to trip failure at aluminum bus-to-circuit breaker connection - field report and photographs
Electrical Panels, How to Inspect in Buildings, safety for electrical inspectors, electrical panel, fusing, wiring defects, defective products. Inspection Class Presentation
InspectAPedia® Home & Site Map - Building & Environmental Inspection, Testing, Diagnosis, Repair, & Problem Prevention Advice: In-depth research & advice on diagnosing, testing, correcting, & preventing building defects & indoor environmental hazards. Unbiased information, no conflicts of interest.
The Mold Information Center: What to Do About Mold in Buildings, When and How to Inspect for Mold, Clean Up Mold, or Avoid Mold Problems
Environmental Inspection, Testing, & Diagnosis On-Site IAQ, Gas, Air Testing, Mold Investigation, Sick Building Diagnosis, Lab Services, & Remediation Plan Preparation - indoor air quality testing, problem source determination, supporting lab work, written remediation plan addressing removal of environmental and other hazards and prevention of their recurrence.
InspectAPedia ® Home & Site Map 
Other methods - not recommended:
The Aluminum Wiring Information Website 
Carson Dunlop's Home Inspector's Home Study Course
InspectAPedia® Home & Site Map
