My Home Inspector Said Aluminum Wiring Will Catch My House On Fire!

Single-strand aluminum wiring was installed in many homes built in the mid 1960's to early 1970's. After a decade of use, inherent weaknesses were discovered with the wiring. Neglected aluminum wiring connections become increasingly dangerous over time and may overheat and create a fire hazard. A good home inspector will always recommend that single-strand aluminum wiring be evaluated by a qualified electrician who is experienced with aluminum wiring problems.

Aluminum has certain qualities that make it an undesirable material as an electrical conductor. These qualities all lead to loose connections which creates a fire hazard. Here are a few of them:

1. Aluminum becomes brittle with age and will fatigue and break down when subjected to bending. Fatigue will cause the wire to break down internally and will increasingly resist electrical current, leading to a buildup of excessive heat.

2. Exposure to the air causes oxidation at the surface of the wire which makes it less conductive. As time passes, oxidation can deteriorate connections and present a fire hazard.  

3. Aluminum is a soft metal and highly sensitive to compression. After a screw has been over-tightened on aluminum wiring, the wire will continue to deform or “flow”. This deformation will create a loose connection and increase electrical resistance in that location.

4. Aluminum expands and contracts with changes in temperature. Over time, this process will cause connections between the wire and the device to degrade creating a fire hazard.

Here are some repair options if your home contains aluminum wiring: 

A. Rewire the home with copper wire: While this is the most effective method, rewiring is expensive and impractical, in most cases.

B. Replace receptacles and switches with CO/ALR devices which are compatible with aluminum conductors.

C. Install pigtails using a copalum connector: Copper pigtails are attached to the ends of the aluminum wiring circuits with a specially designed metal sleeve and crimping tool.  The copper wire is then connected to the receptacle or circuit breaker. Note: These wires should never be connected by simply using a wire nut!

It should be noted that multi-strand aluminum wiring is commonly used in modern construction. This wiring has proven to be safe as long as anti-oxidant paste is applied at the connections which prevents dangerous oxidation from occurring.

My Home Inspector Said Aluminum Wiring Will Catch My House On Fire!  Steve Stenros is the owner of First Choice Inspections. He is a CREIA home inspector with the MCI designation. Clients receive a FREE lifetime appliance RecallChek with every standard home inspection. Appointments can be obtained by calling 888-335-3040.