DIY Doctor UK DIY Forums

I want to put up plastic cladding on a ceiling - on top of polystyrene tiles ('cause there's artex underneath the tiles - taking the whole lot off would take far too long). Can anyone tell me what adhesive I should use? The polystyrene is very firmly attached with something resembling cement; don't really want to lower the ceiling by putting timber across it.

Any suggestions would be very much appreciated.