Here is the situation. New home construction. The tub was not set until after drywall. The tub drain plumbing comes out the foundation in the stud bay beneath the mixing valve. A post tension cable blocked proper routing of the drain from the tub to where it enters the slab. The plumber used a 45 degree elbow to go over the cable creating a small uphill climb in the drain. This basically created a belly from the tub drain to the 45. On a plane, the top of the 45 appears to be close to the bottom of the tub. Is this acceptable?
I would think this would be an area for debris to collect, eventually cause a clog and that the tub would drain slower. However, my experience with building code is that there are enough “exceptions” that I may have missed something.