I got out the sidewalk chalk and a tape measure, and drew a 6'6" x 4' box on the garage floor, then added a little box next to it to make it 5' wide. After getting the wind bag to lay down in the boxes with me, we agreed that a few more inches on the 5 wide would be nice, so 5' 2" became my interior width.
Actually, I would like to go about 10' wide, and give her her own zip code to sleep in
