Best ceiling option for wetroom with loft above?

[CCoomber]

Just curious about people's thoughts on this I'm currently working on a diy project of a wetroom on a first floor with only loft space abovr.
I was planning to use duplex boards and a primer but wondered since it will be a small wetroom with potentially a lot of hot steam would it be worth adding upvc cladding to the ceiling as another barrier be worth it?

 

[Deluks]

Duplex is fine. uPVC looks crap indoors.
Fit an extractor and make sure it can't be bypassed. Either comes on with the light, or if there's a window (meaning light may not be used) then have a fan with built in humidistat.

 

[RandomGrinch]

Just some additional thoughts...

If you have spotlights penetrating the ceiling, detail them so the vapour barrier isn't compromised and give them an insulation hood.
An inline fan with the vent in the middle of the wetroom area would probably work better than a smaller wall mounted fan.
It's also good to leave a slim gap beneath the door, so any extraction can freely draw in replacement air.