I am replacing the drain in the bathroom lavatory. Is it OK to connect PVC to the existing metal pipe in the wall?

Hey WH...

If you are talking about threading a pvc adapter to say a threaded metal fitting in the wall... then yes... absolutely!

If you are talking about connecting to an older pipe using a flexible clamp... then yes... as long as you use the right clamp (ask about this if planning to use this alternative).

If you are talking about soldering a threaded fitting onto older copper pipe and then connecting a pvc adapter to that... then yes... for sure!

Describe the metal pipe you have.. silver... copper? A picture would also help?

Let us know...

MARK

If you are ".....replacing...." drain, than you should already have threaded female T in the metal pipe. Use plastic male adapter, wrap threads with teflon tape and screw it in. Continue with plastic. Just like Mark said, yes, it is perfectly OK...

I am replacing the drain in the bathroom lavatory. Is it ok to connect PVC to the existing metal pipe in the wall?
Solder on a 1 1/2" copper slip to FIP(female ironpipe thread) to the wall stub out. Now you may transition to PVC using a PVC slip to MIP (male iron pipe thread) with a 1 1/2 to1 1/4" nylon gasket. See image below. Don't forget to wrap three turns of Teflon Tape around the male threads. Good luck, Tom