Popped ceiling nails are a warning sign that your ceiling may well be ready to collapse. The consequences can be a serious injury to yourself, family members or friends. If you see nail popped rings on your ceiling, measure the height variations across the room from ceiling to floor. If there are any variations of 12mm or more this means that there is a seriously dangerous issue and the ceilings can collapse. The ceiling can drop for many reasons, most commonly is the gyprock glue failing particularly from houses built between 2005 to 2009 due to a brand of adhesive that is now no longer sold, water leaking issues or just bad workmanship.