I have a 1950's Florida ranch in Fort Myers, Florida. The previous owner enclosed and finished a lanai and finished the 2 x 6 framed ceiling with 1/2" drywall. They did not insulate it and from April to October it is extremely hot in that room. It is a true flat roof with rolled roofing. I plan to apply a reflective roof coating to the exterior (I read about that in another article), but I need to add insulation to the ceiling. I am a drywall repairman/finisher by trade, so was thinking of cutting a 16" x 16" hole between the studs down the center of the room and either force in bats of insulation or blow in the insulation. The room is 13 feet deep in the direction of the rafters. I think the framing is 24" O.C. but I will verify that.

Am I thinking correctly, or is there a better way?