Electrical Wierdness...

Ok, this has me stumped. Two level home in Livingston, Montana. No problems on the lower level, but every single outlet, every light switch I touched on the upper level, gave me a static shock, some fairly strong.

What could be some potential causes of this kind of thing? It was exceptionally windy that day and the homeowner regularly keeps the thermostat at 80 degrees.

It was suggested to me by another inspector locally that there may be a lack of humidity in the upper level that is adding to the static electricity. Does this sound possible to you?

The house was 2005 built, grounded with a rod in the ground, ufer in the crawl and to plumbing.

I’m really hoping you all have some wisdom for me on this one.



Shag carpets???

Dry air will do it, especially when mixed with shoes dragging on the carpet!

With the cold winter air already being dry, the extra 8-10 deg heat will cause the rh to drop quite a bit. Although the psychometric chart is a curved affair, in the rh’s and temps we live/work in, a bit of a straight line phenomenon is a useful “rule of thumb”:

If you raise or lower the temp of air 18 deg F or 10 deg C without changing the absolute humidity (amount of water), the rh will approximately halve (temp rise) or double (temp drop).

So you can see, when outdoor air at -8 deg F and 90% rh enters the house and is heated to 72 deg, the final rh of this air would be just under 6%!! But this air mixes with house air containing more moisture…but the overall rh drops, hence the need for humidifiers (well in very loose drafty, inefficient houses)

So being in the cold central western states, the rh in the house you inspected could be in the mid 20% range, very dry and encouraging to static electricity.