1. Is aluminum wire allowed?
Short Answer: Yes!
Long Answer: The Canadian Electrical Code (CEC) which is adopted by the Province and included in the Ontario Electrical Code allows the use of aluminum wire in all types of construction at present, as it was in the past when aluminum wire was first introduced.
2. Is Aluminum wire safe?
Short Answer: Yes, but not always.
Long Answer: Yes, if properly installed and properly terminated and used in it’s proper application per the Canadian Electrical Code (CEC) it will operate as safely as copper wiring, but there are more things you need to know.
3. Why Is It Important To Know If Aluminum Wiring Is In My Home?
Answer: There are some technical issues surrounding aluminum wiring so Insurance Companies may want to know what type of wiring is present. If it turns out Aluminum wiring is present, then the Insurance Company may want to know if it has been certified to be safe.
4. Background of aluminum wiring use.
Aluminum wiring was used quite extensively in residential homes during the 1970’s. More specifically, mid to late 1970’s. It was also used in other applications such as commercial, industrial, and institutional buildings. Its popularity resulted from it being cheaper than copper. After the late 1970’s aluminum wire became unpopular because there were some fires and investigators attributed the cause to be aluminum wire related. Manufactures modified the composition of the wires they made which improved the reliability of the wiring and bumped the price a little. The end result was it still was not comparable to copper, so the industry went back to copper. Aluminum remains a legal wiring material/method officially, but is not used as a branch circuit medium anywhere currently in Ontario. Also, it is currently not stocked in any of the big box stores in Ontario, so even if you wanted to buy it you may not be able to do so. It is important to mention that the issues with aluminum wiring is limited to solid wire only.
5. Solid conductor/wire vs. Stranded conductor/wire
The contents of this section (#5) applies to both aluminum and copper conductors and is here to enlighten the reader why most conductors are solid while others may be stranded ONLY.
Branch circuits are the circuits from the distribution panel to the various receptacles, fixtures and appliances in the home. Each branch circuit is protected by one fuse or one breaker. These branch circuits for the most part are solid conductors.
Some appliances such as an Electric Range consumes a lot of current. Such appliances need to be served by conductors with larger diameter (that is a fatter wire). Conductors become more difficult to handle the thicker (or fatter) they become. So conductors for heavy appliances such as an Electric Range is made stranded. Stranded wires are naturally easier to handle than solid wires.
6. The problems and consequences with aluminum wiring installs.
Aluminum wire is itself safe…it is the connections that cause the problem. When aluminum wiring was first used the connection points on electrical equipment such as panel board breakers, receptacle and light switches etc had copper terminations. There are two distinct characteristics Aluminum has that differs from that of copper:
- The two metals (aluminum and copper) and expand and contract differently when under electrical load or with temperature changes. Terms you may hear used are creep or cold flow which may cause the connections to become loose. This issue is limited to solid wire. So it does not apply to stranded wire. A loose connection is poor connection.
- Now for a little chemistry. The two metals are not close to each other on the nobility scale. Putting it simple….they dislike each other. So when Aluminum Wires are terminated to Copper Terminals or to Copper Wires the connections tend to corrode. A corroded connection is a poor connection.
Expansion and contraction, or Corrosion all results in loose connections. When the connections become loose this can result in sparking, arcing, oxidation and heat build up and finally the possibility of a fire through the ignition of surrounding combustibles such as the insulation on the wire, wall insulation or wallpaper in the area of the electrical box etc.
Oxidation is the build up of a thin layer of aluminum oxide which creates a thin insulating layer increasing the electrical resistance of the connection and thus increasing heat build up – copper does oxidize but does not act as an insulator and copper does not expand or contract as much when under load as does aluminum.
7. Innovations to address the problems with aluminum wire connections.
As mentioned before, steps were taken to address this problem of aluminum wire connections. The industry came out with dual rated connectors that would accept either copper or aluminum wire. Items with the dual rating were indicated by a marking such as CU-AL, CO/ALR, AL/CU or something similar. This solution offered some relief to the problem. However, with the fires that had occurred its use in the industry basically stopped in the late 1970’s. During this time such things as anti oxidants were developed that would be applied to connections to reduce the oxidation of the connectors but this involved continual maintenance and was too time consuming and therefore not a very favorable solution.
8. What Your Inspector May Say/Do?
The inspectors at Qualitex Home Inspection always look into the homes electrical panel once it is accessible and safe to do so. If there are aluminum wires present in the home, its likely you will see them here.
Once Aluminum wiring is seen, we scan the receptacles and switches with either an Infrared Spot thermometer or an Infrared camera looking for any thermal anomalies. Any and all anomalies are saved digitally.
In our subsequent report, we then state our findings, state any limitations that hinder the inspection, and we provide pictures. We make what ever recommendation we think is appropriate based on our expertise and training.
9. Where does the Insurance Company enters the process?
The insurance Company is not interested in you. They want to protected their money so they never have to pay you. So they may ask that you provide proof that the wiring is safe. This is where you may need to hire a licensed electrical contractor to do just that.
10. If An Electrician Is Needed, What will He Do?
The electrical contractor may need to check all your termination points in the home. That includes distribution panel, receptacles, switches and fixtures, etc. If he/she finds any not up to spec, then those are improved using standard industry practices such as either replacing with the appropriate part, or pig-tailing with the correct wire nuts. Usually, this is all that is required.
11. Do Not Attempt Electrical Work Yourself, Get a Licensed Electrical Contractor
Electricity is invisible. It also can kill you. Therefore, all electrical work MUST be done by a Licensed Electrical Contractor. Aluminum Wiring adds a another level of difficulty or complexity. Even more reason to ensure whoever will be doing the work is truly qualified and have the expertise to do so.
Qualitex Home Inspection services the Greater Toronto Area: Toronto, Mississauga, Brampton, Milton, Oakville, Burlington, Vaughan.