I am renovating a bathroom that is built on a slab foundation. I want to install a stand alone steam shower that requires a level floor to set the unit on. I want to use the space where the current built in shower is located. The plan is to use the existing hot/cold supply lines and drain.

The existing shower was build into the slab foundation. That is, a rectangular hole was left when they poured the foundation. Then a cement bed was created below the slab level and was tiled over forming the shower pan. I want to fill in the existing shower pan so it is level with the slab foundation. I will install new flooring over the entire bathroom. The stand along steam shower comes with a build in pan and sits on the floor. Kind of like a piece of furniture.

What is the best way to make the area level? Should I frame in the old shower pan area and cover with cement board or should I pour cement into the area so just the drain pipe is above slab level.

Hope this makes sense. Thanks for any help.