Is it OK to connect a lavatory drain to the overflow pipe on the tub? Tub and sink are back to back.

Hi Dsmorgan...

Nope... not OK to connect a sink into the tub overflow pipe on a tub. A sink requires its own trap and its own vent.

You can, however, connect into the tub drain past the tub trap and vent if that makes thing easy... ;)

Let us know if you want to discuss this more... O.K?

MARK