what does drywall  weigh
Standard drywall weighs about 3.4 lbs per sq ft per inch thickness. Water resistant drywall (greenboard) weighs about 3.9 lbs. per sq. ft. per inch thickness. Firecode C drywall weighs about 4.2 lbs. per sq. ft. per inch thickness. These are approximations, as the ratio of core vs. covering varies for different thicknesses, thereby varying the exact weights.