Flood Damage Victims

Dear Flood Victims:

I have spent the past 30 years learning all I can about all facets in the electrical field and my exhaustive research and on the job experience allows me to answer the questions I receive with a great deal of confidence. At one time or the other over the three decades, I've also had to deal with the average user’s electrical scenario with a few variations. The major differences are in the wiring method.

In the past, some commercial buildings were wired with electrical conduit piping. Now those pipes have sustained water damage which will ultimately cause rusting away of the wires. This rust will eventually affect the efficiency of the electrical system so in most cases, the wire will have to be replaced. We have had some situations when our customers declined to replace all equipment, figuring the damage was probably limited. In many of those situations, we found that equipment that we didn't initially replace had to be replaced a few months later. It took time for the damage (usually in the form of rust) to show up and for the equipment to eventually fail.

Most of the homes in the Nashville area typically have the standard 12/2 “Romex” wiring. The problem with this wiring is that it was never intended to be exposed to excess moisture or chemical agents. Unlike “UF” cable, Romex is not designed for moist environments or for direct underground burial.

If one were to strip back a short length of Romex wire, inside would be found not only the white, black and ground wires The ground wire is wrapped in a thin layer of heavy cardboard like paper and that, when it gets wet, stays wet for after exposure. Normally this is all covered up in an outer plastic white jacket that covers all three of the wires until it enters a wall box for a switch or a receptacle where it is then stripped back for termination to the device.

If your home was underwater for any period of time, it is likely (if not inevitable) that water has now traveled well inside and down the jacket. If so, the wiring in the walls from at least the high watermark downward is now ruined. The copper wiring will eventually rust even if the home has long since drained and all boxes are dry. Factoring in the additional destructive properties of unusual chemicals in the water, prudence would demand that wiring and devices be replaced.

Simply pulling the wires out of the boxes and letting them dry might be a temporary remedy but it won’t stop the chemical reaction that has already started. It is likely that problems will occur either when the hidden corrosion begins or the outer jacket of the wiring begins to degrade. With that said and based on my knowledge of the field and the damage I've seen water do in other building types, I would certainly be numbered in the group of electricians that recommend replacement of all wiring that was exposed to the water and chemicals. I'd much rather be safe and eliminate the possibility of a fire (or other less serious problems) due to hidden damage.

Wet drywall will need to be replaced to eliminate mold and mildew and that stinky fishy smell. With the walls open, replacing wiring and devices may be a fairly easy and straight-forward task. Also, this might be the perfect time to add any extra switches or receptacle outlets you always wanted to have so there is an upside to this despite all the damage. Of course, it is understood that all local codes do apply with any work you are having done in your home.

If you do not have flood coverage, this kind of replacement can get costly, but in good conscience, replacement of damaged wire and devices is my only recommendation that will allow me to sleep at night.

I hope this helps.


Yours truly,

T. David Rains