On Mon, 12 Oct 2015 11:05:18 -0500, dpb wrote:

On 10/12/2015 10:43 AM, Oren wrote:
On Mon, 12 Oct 2015 11:18:22 -0400, FrozenNorth
wrote:

On 2015-10-12 11:06 AM, wrote:
Hi.
I'm replacing the cast iron 4" sanitary lines to my two bathrooms with PVC. They drop vertically from each bathroom and turn 90degrees to horizontal in the basement. This turn is via existing long turn/long sweep elbows.

Is there any problem if I switch these to short turn 90 deg elbows? I'd like to regain the headroom in the basement and keep these pipes within the ceiling joist level, instead of having these stick out below the (future) finished ceiling level in the basement. I can't find anything in the plumbing codes on this. All advice appreciated.

There is probably no problem doing that, but just in case, use elbows
with a cleanout.

... I'd ensure to maintain proper pitch (slope) in the pipe

And _I_ would likely not remove the sweeps, either...an inch or two of
head room isn't worth the possible hassle imo.
I'd remove the "sweeps" and go with the generally accepted and
commonly used fittings made and sold expressly for the application. Do
make sure your drop is correct - the right amount of slope on the
pipes. Don't figure more slope is better - install according to the
slope specified in code.