In an 2nd floor bathroom I am trying to separate a tub/shower into a separate shower and free standing tub. Is it okay to used the same drain that was used for the tub previously which is 1 1/2" ?
Would there only be a problem if, by chance, the tub was draining at the same time someone was taking a shower?
The first floor has been remodeled so it will require tearing into some walls to run a new drain.
It seems that a new 2" drain should be installed for the shower but I don't know if that is going overboard. I really don't want to have to blow my budget on something that would never be an issue.