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The Problem With Aluminum Wiring In Your Home

What's wrong with aluminum wiring

You may have heard of aluminum wiring, so what is the deal? Why do insurance companies require me to replace it? Is it safe? Can you purchase a home with Aluminum Wiring? Let’s talk about it.

Aluminum wiring is actually used quite frequently in commercial and residential use. However, concerns arise with single-strand aluminum wiring (also known as branch circuit wiring). Multi-Strand aluminum wiring is commonly installed on new homes today and does not have the same concerns were are going to talk about below.

Single Strand Aluminum Wiring/Branch Circuit Wiring is the wiring throughout your home. For example, this is the wiring that powers your lights or outlets.

Multi-Strand Aluminum wiring with anti-oxidant paste.
Multi-Strand Aluminum Wiring with Anti-Oxidant Paste to Prevent Rust Pictured Above

Single Strand Aluminum wiring was mainly installed in the 1970s as a replacement to copper wiring, but it can be found in homes after the 1960s. Aluminum was cheaper than copper at this time, but several issues were discovered later.

Single Strand Aluminum Wiring With Anti-Oxidant Paste To Prohibit Rust
Single Strand Aluminum Wiring With Anti-Oxidant Paste To Prohibit Rust

The Issues with Aluminum Wiring

  1. Aluminum is softer to work with. A soft metal can be easily nicked. A nick can be hazardous, as the current needs sufficient metal to flow. Ultimately, since the metal is cut wrong, the metal can heat up more than other areas. This can lead to a fire.
  2. Aluminum expands and contracts faster than copper. This can lead to weak connections and potential fires/sparks at the connection points.
  3. Aluminum rusts differently than copper. When copper is exposed to oxygen, it creates rust that is actually more conductive. Aluminum on the other hand develops rust that is less conductive. That is why in the picture above there is anti-oxidant paste on the multi-strand wire.
  4. Aluminum has greater resistance. This means a larger wire is needed in order for the same amount of electricity to flow.
  5. Aluminum is less ductile. This basically means the wire can be easily broken.

Repair Options For Aluminum Wiring

The issue for aluminum wiring was at the connection points. So, special connectors were made to be able to handle copper and aluminum wiring:

  • Small receptacles marked CO/ALR or AL-CU
  • Large receptacles (> 20 amps) marked AL-CU or CU-AL
  • Switches marked CO/ALR
  • Twist-on wire connectors (sometimes called wire nuts) marked AL-CU or CU-AL
  • Electrical panels and breakers marked AL-CU or CU-AL were also available.

Replacement To Copper Wiring

This is by far the most costly option, however, it is the best option to receive insurance and guarantee safety. The cost of replacement can be dependent on the size of the home, so be sure to call a few electricians in your area. An area can have very different price points, so be sure to look local.

Remediate the Connections

The second option to repair of this wiring is having an electrician add special connectors wherever there is an aluminum junction. This means every outlet, switch, fan, light, every wire that enters the panel, must have a connector.

Alumiconn Connectors for aluminum wiring
Alumiconn Connectors Pictured Above

There are two types of connectors being highly used right now. They are Copalum and Alumiconn. More information about them here.

Final Thoughts

Aluminum wiring at first was used in the 1960s due to lower cost. However, after a few years, overheating, arcing, and fire concerns arose.

If your home has single strand aluminum wiring you may have difficulty obtaining home insurance or have higher premiums. It is recommend to remediate the wiring or replace it with copper wiring throughout.

Have more questions about aluminum? Comment below or contact us.