You can. .
The 1950s house that I recently purchased has a wobbly toilet.
Expecting a broken flange, I pulled the toilet to find no flange at all! The toilet is simply bolted to the floor with lead anchors and lag screws. The wax ring is “sealing” the toilet’s outlet to a lead closet bend.
Unfortunately, the bend is so tight and oval shaped, it prevents the installation of a suitable expandable sealing flange. So, I plan to revamp the piping with ABS and Ferncos.
Since the piping is in a crawl space and the existing CI is suspended 10-12” below the floor joists I’m wondering… instead of a closet bend off the flange, can’t I simply drop straight down and use a long sweep el to connect to the CI?
So, flange…8” or so length of ABS…sweep el…more ABS…Fernco to CI?
You can. .
[B]No, plumbing ain't rocket science. Unlike rocket science, plumbing requires a license[B]
Fernco is a brand name...what you need is probably made by them, but since the pipe is not underground, make sure to use the proper banded coupling - not the thick rubber fitting with only the hose clamps at the end.
Important note - I'm not a pro
Retired Defense Industry Engineer; Schluter 2.5-day Workshop Completed 2013, 2014