I have installed a trap for the basement shower. How is the best way to back fill the opening under the concrete floor? Should I use sand or the rock base that was removed?

The rocks that were removed will be just fine.

Floydsk

Did you VENT the new shower drain? If not, then you could have issues with sewer gasses escaping into the house. Here, you won't be super happy to have a nice finished bathroom/shower and have "unexplained sewer odors" (not so unexplained now, huh?)... ;)

Care to discuss... let us know, OK?

Mark

The vent pipe was installed during the original construction.

Honestly, very happy for you... I hate breaking that news to people!!

I fill my shower drain areas with the same rock as mygirlsdad77 said would be fine... I add a coffee can around my drain and then cement the area in.

Then, after that has dried and if I am installing a prefabricated shower floor, I mix some structolite perlited gypsum product and set my shower base in place... levelling from front to back and from left to right... shim as needed.

A copper or vinyl shower pan is a different installation, of course!

Good luck!

Yep, we all agree same old rock fill is fine.

A coffee can. Now there's an idea. I think Ill use that. Thanks Mark.

Thanks for the coffe can idea.