I have a 2005 townhome in SoCal that is extremely well built - everyone I have had do work on the house has commented on it, so I suspect that what I am seeing is up to code:

I am installing a doggie door in an exterior (stucco) wall. After I cut through the interior sheetrock and pulled out the insulation, I discovered a pair of rather fine (like the highest string on a guitar) bare wires running in parallel, about 1/2" apart right across the hole. They are inside the tar paper for the exterior wall, but run outside the studs. I can't tell where they go after they disappear to the left or the right.

Any idea what these wires are? The only thing I can imagine is that they might be speaker wires for an outdoor speaker setup? But then why wouldn't you use a twisted pair? Perhaps they are doorbell/intercom wires? We also have an automatic (fire) sprinkler system, so I don't want to cut anything important...

Thanks for any ideas!

Oh - and I should add that the wires look like they are probably aluminum - they are a dull gray color, not shiny, and they look to be just a simple wire. Almost looks like something you would hang a picture with, not run through your wall.

E string is pretty small. These are non insulated bare wire? I have built some homes, remodeled a lot and have never seen what you are describing.

Could be a door bell wire. Try using a non contact electrical detector, or simply push the wires up out of the way.

A friend of mine figured it out - the exterior is stucco, and they built it by putting up the studs, wrapping them in tar paper, and spraying the stucco on - there's no plywood or chipboard sheeting. The wires were run horizontally across the studs just to support the tar paper during the construction process - when I reached my hand up the wall, I found several more wires just like the ones I found before. So the wires aren't serving any purpose now - they've been cut, and doggy door is installed. Now I just have to get my dog on a diet so she fits... :)

No way stucco would be supported by tar paper. Possibly wire mesh substrate.