I'm finishing my basement and want to install a small bar sink. I have an open T in my main stack that I plan to run the sink drain to. That T is 23" off the floor. From there I'll need to run horizontal 12 feet down the wall. I want to put as much slope in that line as possible (min. 1/4" per foot). What depth below the bottom of my sink basin do I want my drain line to enter/exit the wall to allow room for the p-trap and an air admittance valve? I'm picturing a 44" high counter top and a 6" deep sink.

Also, what size line should I use... 2" or 1-1/2"?

Thanks.

Hi Emturg. You can run that bar sink 1.5 inch pipe.. no problem.

So, Tee fitting is 23 " plus 12 feet at 1/4 " minimum equals 3 inch of pitch.. so end up at 26" to center minimum. That should work fine for the trap and the provent (or AAV) with a 44" counter top with six inch depth sink.

Cleanouts are key here... one full size under sink.. one just before connects to tee fitting at stack (via a dandy cleanout (also called a test tee)).

Let me know if that is clear. If this helped, please RATE THIS ANSWER by clicking on rate this answer button at upper right. Thank you.