To the real estate editor: From your July 3 inquiry regarding aluminum wire in residential homes, I would like to reiterate its potential danger without proper installation.
Aluminum wire has far more resistance to electricity than copper. Because of this the wire has a tendency to shrink and loosen at its points of connection, such as breaker boxes, outlets, and switches.
(More responsible contractors will only use aluminum for their lead-in wires at the main panel -- from the meter to the house -- because this is the biggest wire and most costly if wired in copper.)
When the aluminum wire loosens at a terminal connection due to terminal shrinkage, the intense heat that is created will cause an "arch" in the box that will subsequently lead to a fire.
If the contractor has not already done so, the simplest and safest way to prevent shrinkage and loosening of connections, short of rewiring with copper, is to clamp steel lugs to the ends of the aluminum wire at all connecting points. The steel lugs are then bolted into place and become the new connection. They are secure and will not loosen as the resistance of the aluminum wire continues to deteriorate.
The only other way to prevent "arching" of aluminum wire is to retighten all the connections throughout the house every six months -- which is a pretty extreme job. A small investment in steel lugs and a day's labor will make this chore unnecessary and protect the home from electrical fire.
Unfortunately, the wide use of aluminum wire in residential and commercial buildings is due to economics. Aluminum is far cheaper than copper. Because our electrical codes do not recognize the potential hazards of aluminum wire, it is a legal and simple area for contractors to cut corners and save construction costs at the expense of the new owner.
Even when the life safety code of a state (Ohio) calls for sprinkler systems, smoke-detection devices, and alarms for the prevention of fires in such places as homes for the elderly, the danger of aluminum wire is never addressed and the incidence of electrical fire goes unchecked.
Needlessly and dangerously our bureaucrats fail to react. J. Scott Rogerson Greenwich, Ohio