I'm putting in an Americast Stratford Tub. It's a soaker, not a whirlpool, and it will be used as a shower as well. I'll be doing a typical recess installation with three sides of the tub resting on 2x4 stringers attached to the existing wall studs and the front side resting on a short (knee) wall. The tub is then dropped in. This tub is supported buy the three stringers and the short wall -American Standard says no additional sump support is required.
When I build the knee wall, should the tub rest on the 2x4 wall top plate, on backer board on top of the 2x4, on top of the the tile on the backer board on the 2x4, or some other option?
To put it another way, do I rest the edge of the tub on top of the tile or rest it on the wall and lay the tile up to the edge of the tub itself?