Hello all,
It is my understanding after reading several threads on this site that when installing a shower over a slab of concrete you need to leave a hole "Dap-out" about 14x14 so you are able to perform maintenance on the P-Trap if needed. But once the shower is installed over the P-Trap how would you be able to access the P-Trap without moving the whole shower from over top of it?

It's not really for maintenance, it's so it can be moved back and forth for adjusting when installing. If you want it to be future maintenance enabled, you'll have to make an access door on the other side of the shower wall.

Thank you SpaceRatt, I may have more questions later about this access door!