Finishing bsmt adding full bath want to know if I can and how to tie shower and tub into existing floor drain

Hi Greg...

If you are adding a full bath to the basement you will probably be better off connecting the tub/shower into the sink drain below the floor. This way you can use the vent from the sink to act as a wetted vent for the tub/shower AND the toilet... ;) The sink drain and vent would need to be run full size 2" all the way to connect into a 2" or larger vent in the building.

Finally, not all codes allow for wet venting so be sure to check your local plumbing codes to be sure it is allowed.

Let us know if you have questions on this... O.K?

MARK