When I started the garage addition (In Addition, 9/18/13), I didn't really have any plans, just scribbled some numbers on the back of an envelope to estimate the lumber. As for the floor, I figured on leaving it gravel. Well that left a lot to be desired, so decided to put in a real floor. My neighbor Butch mentioned how he had laid all weather plywood on top of gravel in his rental garage, so that seemed like a way to go.
First had to dig out some of the gravel to lay out the floor joists: