Many questions arise when Aluminum and Copper are wired in a home. How do I investigate if my home has aluminum and copper wiring for sure? What do I do when I have electrical wiring that mixes aluminum and copper together in my home? Is this really a safety hazard? What are the steps I will take to make my home safe? What is the cost? Why does my home have this electrical wiring system?
The safest way is to take off the outlet or switch face plate and look on the side. On the terminal screw on the side of the device, if you see aluminum and not copper then you have aluminum wiring on your branch circuits.
As electricians, we take off all the dead-front covers on the panels. We are then able to see aluminum on the breakers to the branch circuits.
There are several problems with this aluminum and copper wiring method. One problem is that the two dissimilar metals are mixing together on a device. Another problem is all the newer devices, such as, outlets, switches, smokes and carbon dioxide detectors are not rated for the Aluminum and Copper metals to have direct contact.
This is a fire hazard! Aluminum is not a great conductor for electricity on branch circuits. It becomes soft and expands causing melt down.
The National Electrical Code 2017 Book (NEC) in chapters 100 & 300 discussed the issues and solutions.
There are only two solutions:
1. Rewire the whole home. This is the best method, but it is not the most cost effective nor the most feasible way in most situations! Who really is going to take off all the drywall to access and re-feed the wires? Now, if you have no grounds in the home and have Copper CLAD, this is a great solution to change both at the same time.
2. Take two patented materials to pig-tail splice the aluminum and copper together to the devices. This is the most cost effective way! It is very important that the U.L. Listed Devices, (AL/CU, AL/CO and ALO devices are not rated to be used) and proper method of installation is done by a licensed, insured electrician. This electrical contractor should be well experienced in this method. Don’t hire a handyman or even an electrical contractor who only deals with new construction. A “DIY” approach is putting diox into a wire cap. This will NOT work! It is also illegal, will cause a fire and will dry out.
A whole home re-wire can be expensive. It really depends on the size of the home and the jurisdiction you live in.
To give you an idea, the pig-tail copper splicing method cost involves material and installation. Yes, it is time consuming, but way less than re-wiring a whole home.
What is needed are the U. L. listed devices for aluminum. For this to be done correctly, we need an U.L. Listed switch, copper wire and two ALM/CU devices. For cost of this one opening with one device is the same price as two Venti Starbuck Caramel Macchiato Drinks. That is $12.00. That is just for material NOT labor! An average 1,800 square foot home has 80 switches and outlets, without lighting & dimmers, It would be about $960.00 in JUST material, you have to add labor and any extras. At this time, you want to change the style of color of the device, this is extra cost. For example, toggle switch verse decor switch.
1. Ask your electrical contractor what they typically wire and what is their experience and specialty in?
2. What method they are going to use to rewire the home?
3. Are they licensed, insured and willing/able to provide you documentation?
In the 60s and 70s, the high cost of copper prevented its use in residential wiring. The home building industry decided to come up with an alternative to copper wire. It was aluminum. Even though, aluminum has many downfalls, it was used and it was cheaper and eventually became mainstream.
Aluminum and copper mixed appears to be a simple problem and requires a simple solution, but be aware customers. There is a specific method that needs to be done to install correctly the aluminum copper splicing. If done improperly, you are wasting your money or even burn your home down.
As serving as an electrician in Northern Colorado & Northern Suburbs of Denver, Peterson Electric, LLC has done a whole bunch of these aluminum copper homes. It one of our favorite jobs to do. We are installing with perfection to keep you safe in your home, so you will not have to pay for it to be done ever again! We would be happy to give you an estimate on the repairs for aluminum copper wiring.
