our sitting room ceiling crashed to the floor during the night - the insurance company says that they will cover us for damage caused but not for the ceiling as this is down to maintanance - is this correct in all circumstances?
Your contents policy should cover damage to the contents. If there is any cover for the ceiling itself it will be in the buildings policy. Whether there is cover will almost certainly depend on what caused the ceiling to collapse. If there is no external cause (such as the recent earthquake) then there is probably no cover - policies don't cover all eventualities unless they say so, only the situations they say they cover.
Quite so. There's no good reason for a ceiling to just collapse unless for one of the reasons mentioned. Its either poorly maintained, been weakened by some factor like an earthquake (unlikely in the UK) or having holes poked though it or wasn't designed for the weight above it.