Plumbing question with our residential basement remodel

 

Plumbers get paid big bucks and know the plumbing codes. (Like P3107.3)

A 2" pipe can handle 6 drain fixture units. From what I see, you currently have 3 DFU... half of the maximum. Where each drain enters is not a issue. It could be above or it could be below. Doesn't really matter. Code says the fixture above your bathroom sink can be no more than 4 DFU... you have 2... half of the maximum. Nothing to worry about.

18" is the standard rough in height for a sink. Only reason it would be different is if you will have some special vanity, like maybe one that is on legs and has a shelf that would interfere.

 

I'm not a plumber but I agree on the kitchen sink connection. I was under the impression that with a connection like that the kitchen sink could siphon the water out of the bathroom trap.

I would have liked to have seen two 45's instead of that 90 on the kitchen drain line.
That 90 could be tough to get a snake thru.

 

If anyone would like to reference P3107.3.... here is the link.

https://codes.iccsafe.org/public/doc...apter-31-vents

 

I agree, the kitchen above should tie in under the bathroom sink. Where it's tied in now, it's technically a wet vent, which isn't allowed.

 

P3108.4 - when Vertical wet vent is permitted. (Same link as above.)