Quick Question - PCV or ABS to existing copper pipe?

[EricaC]

I think this is a simple question, but I am installing a new shower as part of a bathroom remodel. The drain pipe that is currently in place is 2" copper. The shower that I'm wanting to purchase has a choice of drain material - ABS or PVC. Will one be easier / better / cheaper to make the transition to copper?

Thanks!
-Erica

[tbplumbloco]

pvc would be the choice of most pro's,the transition coupling should be a mission band coupling or no-hub coupling that is designed for 2"copper by 2" pvc/cast iron.Copper pipe has a slightly smaller ID than pvc and therefore the transition coupling is thicker for the copper side of the coupling.Cheaper is not always better.

[Cass]

Yes PVC.

While the copper does have a smaller ID it is coppers smaller OD that is the problem and requires a specificly sized banded coupling that is made to go from copper to PVC. They can be had at any good plumbing supply house.

[Bob NH]

Since the copper has smaller ID, does PVC to copper violate the "never larger to smaller" practice, or does that apply only for changes in nominal size?

[Cass]

No that wouldn't apply as 2" copper is 1.98" ID and 2.125" OD. . The only time the larger to smaller applys is when changing nominal sizes, like you said, like 4"-3" or 2"-1.5". 2" PVC DWV is 2.375 OD .

[Gary Swart]

I don't think PVC is any better that ABS, some areas don't have ABS, some use a lot of it. Either one will work just fine as long as the transition is done correctly.