I removed an old shower base and will be replacing with tile. I found that there is a dap out hole around the drain pipe. There is no sign of any water coming from the hole or piping. Because I am tiling, I need to prep the floor with a solid base. I've read some other responses on this subject, but nothing with my exact situation. Is filling the hole with flooring cement the correct thing to do, or should I fill the hole with something that can be removed. I guess if there are any issues below the tile work, ripping up the cement is the least of my issues. Any thoughts? Thanks much.

What did you do about the old drain pipe and trap in the dap out?

The trap must be under the concrete, because it is not visible. There is a horizontal pipe at the bottom of the dap out. Coming from that pipe is the drain to the old shower. I was going to use that existing pipe as the drain for the new shower.

The trap must be under the concrete, because it is not visible. There is a horizontal pipe at the bottom of the dap out. Coming from that pipe is the drain to the old shower. I was going to use that existing pipe as the drain for the new shower.
Something's wrong here. There should be a trap and raiser directly under the old shower drain in the dap-out. If not you'rer going to hafta install one. After you get the trap installed and the trap raiser centered you may fill the dap-out up with tamped dirt to within 3 or 4 inches from the top leaving 2 or 3 inches of the raiser above the floor line and fill the rest with cement. You are now ready to install your shower. Good luck, tom