Hi, google didn't bring up anything obvious- so I thought I'd ask the experts here

I live in a relatively new townhouse-3 years old- and ive noticed that a black residue (not mold but more like soot) has built up on a few of the light switches in the home. It's only on the underside of the toggle (where the word "on" is) and on the housing of the toggle itself and not on the switch plate.

Is this a sign of something I should be concerned about? Possible bad wiring/switches? Or is this normal? I've never noticed this before in my previous homes.

Thanks for taking the time to read this and for any advice.

I've never seen that on switch toggles before either.

I think I'd trip the breaker to one of those switched circuits and take the switch out of the electrical box and see if there's anything suspicious going on with the wires to the switch. See if those wires are connected to the screw terminals as they should be, or just stabbed into the back of the switch housing.

It could simply be dirt. Maybe take a cotton shoe lace and cut the plastic tip off the end. Wait for a windy day. Light the end of the shoelace until it's burning under it's own steam, blow out the flame and the smoldering cotton will provide a steady stream of rising smoke. You can use that smoldering shoelace as a poor man's smoke pencil.

Hold the shoelace near the light switch and see if there's a draft out of (or into) it. If so, it might be that you only need to put a foam gasket under the plastic switch plate to stop the draft.

Sounds like dirt attaching itself to oils from human contact. Sorry but I really can't fathom how a back stabbed device would come into play, ever...

Well, I looked at it this way...

I never use the back stab terminals on switches.
And, I never get a black residue forming on my switch toggles.

So, I figured the corelation was simply too great to ignore.

quote:

Originally posted by Nestor:
Well, I looked at it this way...

I never use the back stab terminals on switches.
And, I never get a black residue forming on my switch toggles.

So, I figured the corelation was simply too great to ignore.

Not saying you are wrong. Great minds think alike. The day I back stab a device will be the day I give my tool bag to my apprentice and wish him the best.

Thanks for the suggestions all- ill most likely have to wait until this weekend to try them

you don't by any chance have kerosene space heaters or frequently burn candles, by any chance?

I would suspect that first if you do. that soot gets everywhere that you don't look.