I have a mirror that is larger than the hole left from removing a medicine cabinet in our bathroom, and I plan to mount it so it covers the hole entirely. I don't want to just leave the empty hole there, though.
I'd prefer not to seal up the hole with drywall as I believe at some point we may put another medicine cabinet in that room. I would like to put some insulation in there and I need something to hold that insulation in place.
Any recommendations? Would some sort of plastic be OK to cover the hole and hold in the insulation?