Hi! I have a 2 piece rough-in for my basement, but I also want to put in a bathtub. The rough-in includes a 3" abs stub out for the toilet and a 1 1/2" stub out drain that is vented. I'm going to have to break into the concrete... where is the best place to drain into (p trap then into the 3", or p trap then into the 1 1/2)? Also what would stop the toilet or sink from paritally draining into the tub? Thanks.

Hey jim,

You will bring the 1 1/2" up 18" to the center of a 1 1/2" drainage tee and stub out for the lavatory. From the top of the tee you will extent the pipe out the roof for a vent. The tub will tie back to the lavatory drain where it will be wet vetted. Then tub will rough in about 15 1/2" off the back wall to the center of the traps raiser and 1 1/2" off the front plate. You will also need to cut in a 12" square hole in the cement for a tub dap out where the trap sets. Good luck, Tom