1-1/2" vs 2" for bar sink?

I'm helping a friend with his DWV layout.



Looking for a Pro's view on whether we could use 1-1/2" vs 2" on the run from the 10"x12" (no disposal) bar (prep) sink to the 2" kitchen sink line.

Note, we have to transition five (5) 2x10 floor joists to access the 2" run. Technically 1-1/2" will work, just wondering what everyone's experience has shown.

Thanks,

Mario

Where are the traps? Every sink needs a p trap and vent. I see the AAV for the bar sink, and that may be OK, but the kitchen sink with the DW and disposal must have a trap and there must be a vent.

HE is NOT revising the sink and disposer so that is immaterial to the discussion. 1 1 /2" is "technically" okay, but functionally, 2" will perform better over the long run. And you will appreciate the difference when it plugs up and you have to snake it. This will occur much sooner with 1 1/2" than 2", also.

hj said:

1 1 /2" is "technically" okay, but functionally, 2" will perform better over the long run.

Click to expand...

Thanks HJ. I had read this before somewhere in the forum. Just thought I'd throw it out there and confirm it.

Mario

Like hj mentions. for a bar sink, 1.5" passes code, but it's also half the volume of a 2.0 pipe. Cost is almost the same for both pipes.