I am installing two bathrooms side by side on a common three inch drain line. I know the closet bend has to be 12" from the wall. Bathtub drains, apparently, are two inches from the same wall and 16 inches from the perpendicular wall. But all the "P" trap combinations extend the drain about 8" from the wet wall. I know that the trap can be swiveled. But this would change the measurement from the perpendicular wall. Is there some solution I am not seeing? Any suggestions??
Thanks for any answer, BR