Ok so I’m framing the tub surround for a bathroom remodel, in particular putting in the plumbing wall that will be one side of the tub alcove. I measure 5′ from outside wall, along each floor joist, for the area the tub will have to slide into. Problem: the resulting measurements are not a straight line! It looks like the outside wall is bowing in, not good for getting a 350lb cast iron tub to slide in. If I do a straight line for the plumbing wall, from the start of the area bounded by the plumbing wall into the tub alcove, I get about 5/16″ gap between wall and tub at the worst point; I’m told to stay within 1/8″. Perhaps I could put a small bend in the plumbing wall at the edge of the tub surround, but I plan to run DW the length of the plumbing wall (Kerdi and tiles over it for the tub surround).
Am I doing something wrong? What do the pros do?