Can I put 1/2" plywood on top of cement under a prefab shower pan?

[Alecstar]

I am in the middle of putting in a shower pan where a tub use to be. I have had to jackhammer for the plumbing and its not been fun. The problem now is that my plumbing job is 1/2" too high. It's all cut and glued. I am installing an Oatey 42150 and I need to raise it. I wish they made the same unit that wasn't so tall. Right now I just want to put plywood over the cement to raise the pan up and I'm good. Is there any issue with that or are there any precautions/prep work to be done? I don't want to redo the plumbing because its already resting on concrete and that would mean a load of work. My slab seems to go on forever. I am literally digging a hole in concrete. Thank you.

 

[Rocknroj]

Feeling your pain of no replies.. so my $.02.. cement holds moisture and you are asking for rot.

Not sure exactly what you are trying to do but if you are trying to build up perhaps cement backer board.. concrete mix, self leveling cement all would be options.. Sure there are more.. Anything but plywood on a slab.