First I want to say thanks for all the helpful information I have found on this site in the past few weeks. I am a Carpenter by trade, and we are building a new house, and I plan on doing the plumbing. I have moved a little plumbing before in a bathroom remodel, but this will be my first under a slab, so I would like some opinions on my layout. This is for the Bathroom, house located in Central Arkansas. I just have the pipe stuck together in order to take a picture and have extra length on each piece for final fitment. Vents will tie together in the attic and exit as a 3". Also, is there a minimum height that the risers need to be on the commode and shower drain? I plan on using a 4"x3" closet bend for the commode, I just havent gotten it yet.