I have removed my tub and am installing a curbless shower. Will be using a linear shower drain (Laticrete) which has a 2" discharge. Problem: existing sewer pipe is 1 1/2". Code, AFAIK in CT, is 2".
Existing galvanized sewer pipe threads into a (galvanized?) 1 1/2" x 2" coupling/ bushing which is leaded into a 3" x 2" CI bushing/ bell which is leaded into a 4" CI Tee.
I would remove the 1 1/2" galvanized pipe by cutting it close to the coupling and then cut it parallel to the pipe at the threads a few times and section it out. I can then melt/ drill/ remove the lead seal and so remove the 1 1/2" x 2" coupling/ bushing, but what do I replace it with to reconnect the new 2" no hub cast iron pipe?
Someone on another site suggested caulk. That may be fine but I have never heard of caulk being a proper plumbing joining material. Perhaps "caulk" is plumber"s lingo for a common material/ method. I dunno!
Replacement has to be cast iron for sound deadening purposes as pipes are in Kitchen ceiling.