Shower to sink, bath to shower

[Trons]

I am remodeling the master bath and need to make some changes. I am converting the existing shower into a lavatory and changing the existing bath into the shower. I am in Maryland with the NSPC as the enforced code.

Based on the picture, I have a couple of questions that I would appreciate any input on:

- The far left pipe is a vent. It extends left into the wall, turns 90 vertical, and extends up through the attic to tie into a 2" vent through the roof. From what I have read here and some of my books, this is a wet vent that is venting a single bathroom group. Is that assessment correct?

- The fixture on the far right is the old bathtub that will be switched to a shower. Code requires a 2" pipe, so I have to change the whole pipe. The way the current pipe crosses over and bends back into the drain seems odd to me. Is it standard practice? When I convert it to 2", should I connect it the same way or differently?

 

[hj]

It was NOT "standard practice" because it was NEVER allowed to be installed that way, and you CANNOT install the new drain like that.

 

[Sponsor]

 

[Trons]

It was NOT "standard practice" because it was NEVER allowed to be installed that way, and you CANNOT install the new drain like that.

Thanks HJ.

If I remove the goofy cross over from the far right connection (old tub, new shower) and leave the rest of the vent/drains in place, it should be fine, right? It would be a standard horizontal wet vent (I think the 1.5 in vent may be too small, but I will check the code on that).

My plan is to vent the removed connection separately through the roof and then connect it to the horizontal drain between the WC and the stack. It would be its own "branch" basically.

I am still trying to figure out the right language, but I think I am getting the concepts. Please shoot me down if I am screwing it up.