I've got a switch box on a wall, it was originally meant to be a three-way with the switch outside, but that is not necessary and right now it is just functioning as a pass-through. I know you can't plaster over a junction box as it needs to be accessible. But I've read that you can plaster over the box if you permanently join the wires together by either crimping or soldering with heat shrink. Is this correct?
Further, if I do solder the wires and heat shrink them, can I apply plaster directly over the wires? Or should I put in some styrofoam/drywall as a "backing" for the plaster over the wires inside the junction box (we have fully plaster walls over brick).