Which of the points 1,2,3 is the best to connect the drain of the new sink in the below picture?
The green pipe you see in the wall is a dry vent (it will replace the vertical grey vent you see in the picture)
The white pipes are 1.5" ABS and for the common section I would assume it is 2" (for now it is under the slab, I can't see it)
To avoid breaking more floor I could run the drain for the new sink through the wall and land near the shower drain end and add a common dry vent there. Is that a viable option?
Best Answer
I would use a wye fitting on pipe # 3, run pipe coming off wye (45 degree angle) and use and 45 degree fitting to line up with center line of new sink,use a medium sweep to turn up clean out tee and then 2x2x11/2 santee at proper height Approximately 20” from floor of bathroom . Run vent up wall ,over and above finished ceiling and tie into new dry vent of same size or bigger