Drywall sheets question
Regular 1/2" is fine for 16"o.c. framing. You need to use 5/8" for your 19"o.c. framing. Fire rating is not generally an issue for residential construction unless it is in a garage area (ceiling in a "drive under" and sometimes the "party wall"). The 1/'2" "high strength" IS a specialty item and would likely be a "special order" even at a drywall supply.....
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