In order to remove a shower wall that contains the shower drain vent I need to modify the shower drain.
The photo shows the existing plumbing:
1. A washer drain, trap and vent. This routes under the shower pan and down its own pipe under the wall to be removed.
2. The existing shower trap that routes to its own drain and vent at the wall to be removed.
3. A vent from the downstairs toilet ( not visible in the photo but in the center of the back wall)
Can I cap off the drain #2 in the floor under the wall to be removed and "T" the new drain into drain #1 under the shower pan?
If not. Any suggestions?