Walls and Ceilings - Ceiling Water Damage

I need to repair a ceiling that was water damaged from an AC unit leak from the attic. The leak has been repaired, but the sheet rock has fallen (about an inch) away from the metal studs. It has been temporarily braced with a T to keep it from falling on the floor. I have never worked with metal studs before, and would greatly appreciate any feedback on how to repair this. someone told me that there are special screws made for securing sheet rock to metal studs? I am hoping that the water damaged area will be small, but I think that when drywall gets wet for a certain amount of time, it loses any ability to hold together, and must be replaced. Thanks, RH

If the board has sagged to the point you need a brace to keep it from falling off the ceiling, it needs to be replaced. Any insulation above the ceiling is most likely shot as well. Check with a local drywall supplier, they make self tapping drywall screws for use with metal studs, if you can't find those make sure to get fine threaded screws.

So I need to replace the fiberglass insulation also? I was thinking water would not hurt that stuff, I would think that it would just dry out after a while? Then again it might get moldy? or lose its R-value?
You dont think I could get these metal stud screws at Lowes or Home Depot?
This is a commercial type building with 10 ' ceilings, so it must be 5/8" drywall, hopefully it will just be about a 4x4 section to replace, I plan on having a helper with me, as it seems like a 2 person job.
Thank you for your reply, RH

One other thing I wanted to ask you,, do you think there could have been any damage to the metal studs from the water leakage that I would have to replace?

You should be able to find the fine thread screws at the local big box store, but you'll most likely have to go to a drywall supply to find the self-tappers. Unless the water leak problem has been ongoing for quite awhile before the repairs were made I doubt the studs will be hurt. If there are obivious signs of rust or corrosion, I'd most likely just hit it with a wire brush to clean most of it up and get the loose junk off, then give it a quick coat of rust-o-leum or other rust inhibitive paint/primer bfore covering it up. Good luck. ;)