i have a house that was built around 78 or 79 and it has heated ceilings. there appears to be a 4 x 8 sheet that has broken along a seam, its hard to tell because of the textured finish. i have basic experience hanging drywall but where the panel is dropping i dont see any drywall screws like i think i should and im afraid to screw it back up because i dont know anything about heated sheetrock. is there a danger i could damage the heating system? thanks in advance for any thoughts.