covering polystyrene ceiling in games room

[lindyloo]

Hi, am new to this site and looking for some advice please.

Have insulated walls of a games room (chalet style) with insulating rolls and thin mdf but have put polystyrene sheets on the ceiling between the 'beams'. Now I need to put something over the polystyrene to cover it. Not much there to nail anything to.

Has anyone got any suggestions please? Would hardboard be the best thing. The room is 18' x 12'.

Thanks
Lyn

[welsh brickie]

its best to nail wood battens to each side of the beam and screw plasterboard on top.Polystyrene on ceilings must be covered with a non flammable material.