self tapping screws thru gyp board
 

self tapping screws thru gyp board
i have a pump room with a ceiling framed of light gage metal studs and 2 layers of gyp board on the bottom. the mechanical guys are running a 6" pipe below the ceiling. the ceiling is a one hour rated assembly. can i use a self tapping screw in this situation through the gyp board and into the 16 ga metal stud. the screw through the gyp board is unsupported for 1 1/4". are they going to have trouble installing the screw? can i be certain that the screw will obtain its design tensile strength? thanks.
off the top of my head the only requirement i recall is the minimum screw penetration into the metal studs. so long as you achieve that you shouldn't have to reduce the tension capacity. you will most likely be limited by the pullout of the screw anyway.
it has been a long time since i hung drywall to pay the bills but we only ever used regular drywall screws even when it came to hanging sheets on metal framing. i don't think you need any type of self tapping unless the gage is thick.