DIYbanter - View Single Post - Electrical flash behind light switch plate

wrote:
I am wondering if this is normal. I can see flashes of light sometimes
when I flick on various light switches around the house. It's
intermitent but most noticeable at night when there is little light in
the room. I am nervous this is going to start a fire. Spoke with the
developer they said it's normal. Any thoughts?

Question: How old is your house?

If it was built in the 70's you might be dealing with aluminum wire.
You could also be dealing with aluminum wire and a light switch rated
for copper, instead of switch with a CO/ALR or the older Al/Cu rating.
Aluminum wire is notorious for loosening because of the warm-cool
cycles with use. If the connections loosen sufficiently they will arc,
and in some cases (like in our bedroom) quite spectacularly.

Steve