Originally Posted by drewdin
yes, there # 8
Ill look for one of those calculators. What does a sheet of 1/2" blueboard with plaster on it weight?
"standard 1/2" drywall that is used in interior residential construction generally weighs about 1.6 pounds per square foot, totaling 51.2 pounds for one sheet. "
so with four screws/sheet each screw should pull out at >51/4 x 4 = >51 lbs. There's "working load" computed with some built-in safety factor, and "ultimate strength" where you decide the safety factor.
You are more diligent than almost all DIY'ers. Good.