Thanks Wayne for that mockup!You could do it like in the attached drawing. The drawing is an elevation, i.e. up-down the page is always vertical. Note that the vent takeoff for the shower dry vent has to be a combo, but you've drawn a san-tee on its back; that's not allowed under the UPC.
The 2" shower trap arm (from trap to vent-takeoff) is limited to 60", and the 1-1/2" lav trap arm (from trap under the sink to the san-tee) is limited to 42". Each trap arm is also limited to one pipe diameter total fall. Oh, and if it's more convenient to jog the vertical section of the 1.5" lav vent or drain (since your original drawing had the san-tee farther to the left), you can do that with a pair of 45s.
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Yes Combo after the P trap (looks like a sani tee but with a longer 90) I think I know what you mean. Thanks for that tip!
However, I'm not sure I have the maneuverability to do a vertical stack off the shower P trap the way my main line is oriented. Here is a top view of the bathroom layout and the mainline is in black ink.
I can however do a short sloped horizontal run and use med/long 90s like below:
I understand it's not to code but I'm not getting inspected so I'm not worried about that. But will this way work as well or will this cause some sort of issue down the line?
For the Lav/sink area, I've considered that option as well and believe me that would be the cleaner and proper way, however it will require me to jack hammer a ton of footing out and I was worried I'd accidentally hit the main line abs and make things worse since they encased everything in concrete. (Super deep footing under an interior wall )