Buying or Selling St. Louis Real Estate, here’s great advice!

Another great article from our guest author and building inspector – Harry Morrell.

What's behind door one! Home inspectors look closely at each component of a home very carefully during the inspection. However, no component is more closely looked at than the electric service. Faulty wires and their equipment are the number one cause of house fires. No inspector ever wants to get that phone call saying a fire occurred in a house recently inspected as a result of faulty wiring.

Aluminum wiring in residential construction was installed in thousands of homes across the country mostly between the years of 1968-1972. Aluminum proved to be problematic both by reduced current carrying capability and mechanically at the connections. Aluminum has a greater tendency to thermal expansion than copper. As current heats an aluminum wire it can expand out and around the contacts of a terminal. When the wire cools, the aluminum contracts, leaving small gaps between the conductor and the terminal. An arc can come across these gaps when heat is produced. Fire may result from this event. Of course this is the worst case scenario, but it only takes one or two of these events before the code steps in, puts their foot down, and does not allow aluminum to be installed in residential construction.

So, how does your inspector deal with the aluminum wiring issue in the year 2007? It is not as simple as calling aluminum wiring defective and recommending replacement. That would bring a major dent into residential real estate transactions across the country.

Here are some guidelines in reporting and inspecting aluminum wiring;

Is it aluminum? The inspector must identify the conductors properly. Aluminum is a shiny silver color and should not be confused with copper clad aluminum or nickel or tin coatings used on old rubber insulated conductors.
Is it solid wire? Solid wire aluminum must be reported, typically used on lower branch circuits. Stranded aluminum conductors are perfectly acceptable and are used and installed in new homes at the upper branch circuits and service entrance conductors.
Is it properly protected? Circuit breakers rated for aluminum must have a label stating “Cu/Al” visibly marked on the breaker. The breaker must be the correct size to protect the aluminum. In general, service conductors will be two sizes larger than copper and lower branch circuits should be one size larger than for copper.
Are the terminals tight? While this practice is beyond what home inspectors do during a typical real estate transaction home inspection, a home inspector may recommend an electrician to check the terminals with a torque screwdriver if visual conditions warrant such, especially if old technology aluminum wiring is present.
Was anti-oxidant applied to terminals? While not strictly required by code, the presence of anti-oxidant at all terminals would be an indication of a higher level of quality in workmanship and installation.
How is aluminum terminated at devices? Cover plates must be removed to determine if the receptacles are CO/ALR types, or if the receptacles or switches have been pig tailed. Some inspectors may inspect a representative number of outlets and switches, some may do the whole house for an added fee, or some may recommend an electrician service the whole house to ensure safety. A good home inspector should be able to total up all the circumstances and make this call in a non alarming manner.
What are the basic options? In a nut shell, starting with the most expensive fix first; (A.) Pull the aluminum and re-wire the entire house. (B.) Hire a contractor to install cooper pigtails with and approved methods, such as Copalum crimps. (C.) Replace the receptacle outlets and switches with CO/ALR types.

Aluminum wiring can be a deal killer if not reported correctly or handled in an alarmist manner. Improvements and upgrades for aluminum service can relieve heartburn on both sides of the real estate transaction before the house is listed. Some sellers may not even know aluminum wiring is present. It is highly recommended that a pre-listing inspection be provided on the sellers end to avoid any last minute concerns before the house goes on the market.

Harry O. Morrill