Cracking up- Old Wiring in homes and businesses. Wenatchee and Quincy Home Inspection Services.
When performing a home inspection or commercial inspection in older buildings and residences it is very important to thoroughly evaluate the condition of the wiring system whenever possible.
I had written an article on tinned copper wires a while back (Tinned wires in the home). This article has a little history on why tinning was performed on copper wires.
On a recent inspection I come across a not so uncommon issue with these older wiring systems.
Rubber wire insulation dates bate to the later 1800’s and was a common insulator by the 1890’s. One of the big issues with these wires is that as the rubber ages it will have a tendency to dry out and start cracking.
Here we have a few example of the happening in the service panel.
The wire sheathing has left the wire exposed too far back.
The wire sheathing above has cracked and a potential for arcing.
Further evaluation of this wiring and its associated connections should be performed.
Because of this issue with the vulcanized rubber insulation the wire industry in the 1950’s began transitioning residential wire insulation from the older rubber insulation to the newly developed thermoplastics (PVC). The PVC did not have the same issues with becoming so brittle and cracking. By the 1960’s we have what we all would very familiar with- “Romex” (NM wires).
Little Romex history, the term “Romex” is like “Xerox” a manufacture trade name that became synonymous with a product type.
Nonmetallic-sheathed cable (NM ), was listed and described in the NEC in 1926. The Rome Wire Division of Rome, NY, had developed this wiring type a few years earlier and marketed under the trade name “Romex”. Now most of us call NM wiring Romex.
“The art and science of asking questions is the source of all knowledge.”
Thomas Berger
NCW Home Inspections, LLC is a Licensed Washington State Home Inspection service located in Wenatchee Washington serving Chelan County, Douglas County, Kittitas County, Okanogan County and Grant County Washington and the cities of Wenatchee, Leavenworth, Cashmere, Oroville, Cle Elum, East Wenatchee, Quincy and many more…
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