marvel10: Loads of alternatives. I would stick to a clean finish such as using plasterboards from 9.5mm (thickness), plaster over it and paint it so it looks like a wall. The attached images show the finish from the usual plasterboards.

jaytime: The best ceiling material is POP ceiling. It's not even an alternative: it's in the class of its own. It is durable, best fire retardant, emits no poisonous substances and very very beautiful to mention a few.
Next to it is PVC ceiling. It might look like plastic but it not truely plastic therefore is fire retardant. It only has some plastic material in it: some are plasticized(PPVC) while some are unplasticized(UPVC). There difference is the quantity of plastic content. PVC doesnt burn as many people misconceive. If u want to confirm, put a piece in fire and watch; any flame?
PVC is not as expensive as POP yet beautiful and easy and takes less time to install(to professionals*) compared to POP. It is light in weight therefore doesnt pose any threat to bad wood/nogging.
It emits no unhealthy agents.
In summary, either POP or PVC is just "cool" in your house.

babatosan:
I hear PVC has poor heat absorbent properties compared to POP or asbestos. Rooms are therefore hotter! Is this true?

marvel10:
That said, if you wish to have work carried out to such standards. Feel free to contact me but I don't do jale o (haggling)...