plumbing rough in of a tub/shower in basement concrete floor?

i'm new to plumbing houses with basements. toilets and sinks are no problem, however, im clueless as of how to rough in a tub/shower. I've heard of tub boxes but i know nothing about them. Where should I place in relation to the walls. i realize once the concrete is poured around it, it's done. I could sure use some help with this. I appreciate any help.

Public Comments

1. The easiest way to figure it out is to remember, the stud wall has to be an inch from the concrete. Then you have your 2 X 4 stud as well. That makes 4 1/2 inches to add to whatever measurement you have for the tub or shower drain. Place your tub box around the centre of that measure and make sure it's at the the proper height.