I was looking at replacing my bathtub with a slightly wider, deeper unit (32" wide over 30") - but space is so limited as is in the bathroom that instead of taking up more floor space I was wondering about going the other way and altering the wall behind the tub. As I'd only need 2 inches more space and don't want to intrude into the adjoining room, I was wondering if I could rebuild the wall other than conventional stud construction - possibly turning the studs 90 degrees so the framing thickness is 1-1/2" rather than 3-1/2", and to give it more rigidity, instead of drywall, using 1/2" (marine) plywood instead of wallboard on the tub side. Is this a harebrained do-it-yourselfer's idea that would have inspectors crying foul? I'd have to work out how it connects to the rest of the framing, and it couldn't take an electrical box (and there'd be no plumbing in that wall), but I've done enough structural work on my house that I'd feel pretty confident in my work.
VMacek