Swap Toilet and Shower Locations
I'm doing a bathroom remodel in which I plan to swap the locations of the toilet and the shower. All of my DWV is ABS and it is located in an accessible crawl space below my single story house. I believe the swap is going to be pretty straightforward but wanted to make sure I'm not missing something.
In this post I will ask about the drain for the new shower. Here is a photo of the existing toilet and lavatory drain. The toilet is 3" on the right, then meets the 2" vent which is also the lavatory drain. Then it flows west to my septic tank.
Now I want to remove the toilet and put a shower drain in its place. Assuming the maximum dimension to the vent is not exceeded, is there anything wrong with doing it this way? I'm hoping I can still use the same shared vent (shared with the lavatory) for venting my new shower and not have to vent it separately.
What's the cleanest way to tie in the new shower drain? It will be 2" ABS. What fitting(s) would you recommend to transition the new 2" shower drain into that existing 3" line (where the toilet currently connects)? The new shower drain will be in the same N-S plane as the toilet drain, but about 18" farther south (away from concrete foundation) than the existing toilet drain.
Thank you for any input/advice.
Variation on this same topic
I am remodeling an old 2nd floor bathroom and want to put the tub on the same branch as the toilet. See the picture below.
I want to put the toilet between the tub and the tub drain. I was thinking of using a long sweep with a low heel inlet to connect the tub to the toilet and then the toilet to the stack. There is a separate vent line by the tub already, so that won’t be an issue. It is OK code in Kansas City. My question is whether this works well or not – I have read that if the toilet is not always at the end of a branch, low volume toilets tend not to get sufficient suction to pull waste all the way through the toilet’s trap. There really isn’t enough clearance to put a wye fitting between the closet bend itself and the stack Tee to connect the tub on the “dirty” side. Any thoughts?