Fiberglass shower base over a slab

[avtuvy]

I am installing a fiberglass shower base over a slab and looking for some information on how to align the waste line with the opening in the shower base.
I am not sure that be measuring the location of the hole on the shower base I will be able to set the wast line in the correct location
I saw in a video clip on youtube that shows using a rubber coupler to help with that and it gets covered and buried is that allowed by code?

 

[frodo]

man man man,,,,,

After, you plumb the pipe to the location you layed out.

install a coupling 2" under the floor level. put a 3 or 4" scrap pipe in coupling
backfill the hole with dirt, to 3" below slab.

mix a 5 gallon bucket of quickcrete. make it a little soupy
pour it on the floor around the drain. set unit on the quickcrete.
wigglt, jiggle, level up the unit. screw the flange to studs.

remove the 3 or 4" pipe. measure correct length pipe, hook it up

did you remember to install basket strainer

 

[avtuvy]

Thanks,
Can I use a rubber coupler to connect the old 2" sewer line to the new trap?
this rubber coupler is going to be under the slab and will be burried

 

[frodo]

dig up old trap, cut it loose. yes you can use a rubber

but....by using a rubber, you will have to increase the size of the hole you dig out

easier, to glue new to old,,,if plastic


it is important. that that unit gets set on a bed of concrete. if not the fiberglass will flex, and over time will break/leak. do it right or do it again in a couple of years