Frameless Steam Shower Doors If Shower Walls Will Be Custom Floor To Ceiling Frameless Glass, What Material Should Be Used For The Ceiling?

If shower walls will be custom floor to ceiling frameless glass, what material should be used for the ceiling? - frameless steam shower doors

We are building a new house (new construction) and they removed the tub and shower master bathroom, a custom version of the shower. The shower is through a wall to wall, floor to ceiling frameless glass door frame and are enclosed. The glass is from a 12 "soffit, which will run from the ceiling, climb 8 ', and inside the shower up to 8 meters. The developer has proposed to plan the ceiling, but is a higher rate of quality drywall as usual. They said they have no ceiling, where sanitation problems in the future would be (which is easier to reach the pipe: a detail is that we have a rain shower head on the ceiling between the top two) seed. I'm worried that the ceiling peeling and damaged by the condensation of steam ...