PVC to ABS tub drain

[robb]

I am finishing my basement. There is a pea gravel cut-out in the concrete slab with a 2" cell core sch40 ABS stub. I have 3 questions:
#1 - I was going to use a sch40 PVC tub drain/overflow set; can I connect to the ABS?
#2 - When I remove the cap on the 2" in the pea gravel cut-out, will there be waste water?
#3 - Do I refill the cut-out with the pea gravel once I'm connected and the tub is in? (I will have access thru an unfinished room)

[Gary Swart]

You will need to make the connection with a banded coupler. ABS and PVC being different chemically, can not be solvent welded together. I say this in spite of the fact that there is supposedly some kind of wonder product that will work on both. There should be no water, the trap is still below your connection point. Refilling with pea gravel probably is really necessary, but I might do it anyway. Often this space has a thin layer of concrete.