Damn, I can't remember how many square. A single panel only weighs a few pounds. According to their literature, clay tile is 700-1100#/square. Ours are the heaviest. The steel is only 98#/square.
Let's see....50klbs/900per square=55sq
5500 at 12/12 would be about a 3500sq ft floor. About right?
800 lb per square weight savings is 8lb per square foot of roof, but over the horizontal thats more like 12 lb per sq foot.