I put a spring clip rack on the bedroom side of the bathroom wall. It’s an interior wall. I put it by the rear outer wall as I didn’t want to run a screw through the plumbing. My walls seem to be about an inch and a quarter thick. I installed awnings over my windows on drivers side with 1” screws. Nothing poked through on the inside. Whatever you do, watch out for plumbing and electrical.
__________________
|