1 1/2 drain from shower to up pump toilet?

[bultwinkle]

I'm putting a full bath in my basement. Saniflo offers a unit that has an 1 1/2" inlet for the shower and sink. The pump is still 1/2 HP,17 GPM.
Will a shower drain on an 1 1/2" line?
The total run for the drain is about 7'. I was planning on running with 2" pipe for the 1st couple feet and then reducing down to 1 1/2" so I can run it in the wall to the toilet (up pump)for a better look.
Thanks

 

[frodo]

2'' for a shower drain is minimum size per code, you need a sani flow with a 2'' inlet

709.1 ipc

d. Trap size shall be consistent with the fixture outlet size

 

[Mr_David]

If you install a bathtub, then you can use a 1-1/2" drain but you still have to vent the tub drain.

 

[Matt30]

At no point can you reduce the size of the drain. 2" for the shower must run to the tank, with check valve installed and proper vent for the trap. The vent coming off the tank doesn't count.

 

[voletl]

As long as the showerhead and any body sprayers are 5.7gpm
or under you can have an 1 1/2 drain.

But good luck finding a inch-and-a-half shower drain.

Also you can't reduce the pipe size if you start with 2-inch you have to continue with two inch