Designing Kitchens and Bathrooms - Basement Bathroom

Hi all,

I'm getting ready to finish my basement. It has a bathroom roughed in. My question has to do with the distance from stud walls to fixtures.

1) Is there a standard distance between the finished wall (stud wall + 1/2" of drywall) and the center of the toilet drain?

2) The second question is a little more involved. How do I determine how to build the walls where the shower goes? Right now, the shower drain tap is buried under concrete because the concrete guys "forgot" to leave it uncovered. The General Contractor came back and chipped it out but then covered it with mortar mix and scratched an "X" in the mortar mix. I am picturing that any prefab unit might include rough-in dimensions to the drain which means I simply decide on my shower now and build the walls accordingly. Since I need to connect from the drain to the buried tap, how much play do I have there and is the trap already part of what's buried? Alternatively, I suppose I can have someone make a mortar shower pan for me, but the same questions apply.

I will do framing and electrical all day, but as you can tell plumbing is not my forte'.

Thanks,
Rob

1. The center of the toilet flange should be 12.5"-13" from the stud wall. The flange should be bolted to the top of the finished flooring (tile?) with only the thickness of the flange itself above floor level. The flange should be close enough to the main stack for venting. A toilet has its own built-in trap.
2. The shower drain should have a 2" trap buried in the concrete. You can check it by pouring water down it and looking down in it for retained trap water with a flashlight. The drain line has to be vented after the trap. Check with your contractor to make sure that it is vented (and the 1.5" sink drain, too). The sink trap will be under the sink of course.
As you said, select your shower, and build the walls accordingly.
Check with your Building Inspection Department for local code, permit and inspection requirements.
Good Luck!
Mike