Doing report question on drain size

What is smallest floor drain size in a shower allowed?
Anyone know?
These things I looked at are like a sink basin size.

Normally 2". 1 1/2" was, and may still be accepted by some AHJ. 1 1/2" drain for tub/shower combo. Under slab plumbing is minimum 2".

Thanks Chris.
Check this out.
Looks like a 1 1/2 sink drain with 1 1/4 reducer.

So that would not be allowed then I take it.
They did not even seal the grout.

Hey Bob That is not a shower drain! I have built many a shower(I am a tile guy) and have seen stuff like that. It looks like a piece a pipe just sticking up out of the pan, probably the the only thing keeping it from leaking is silicone, which is wrong. Shower drains are part of a system and needs to be installed properly.

2" in WI and MN for at least the last 30 years.

This was a paint on a pig flip.
You guys should see the other 300 pictures like how the first floor shower is dumping straight on to the asbestos in the unfinished uninsulated crawlspace or the frozen pipes in the basement bathroom from an open window behind the new drywall.
I would laugh if I was not getting finger cramps from all the red ink I am typing.
Agents Nephew buying(or not).
Thanks for the confirmation on the drains however.

The pain of the home will be forgotten in yet another Dentist trip this morning however so maybe I will request laughing gas.

Bob, The 2" requirement was for below grade shower installs so that it was easily snake able.

A smaller drain may not be such a problem if it can be accessed or is provided with a cleanout fitting.

You have that right, Jim…