I want to add a canopy/roof, about 7 feet wide by 12 feet long to my shed, which is about 12 feet wide by 24 feet long, to store stuff out of the weather. The shed sits on about a foot of gravel that was mixed with fines and is compacted. The floor is six pressure treated 4 by 4 with ¾ plywood floor. My question is the two or three posts I will put in to hold up the end NOT connected to the shed, do I dig down 3 feet below the frost line and put the posts in the ground or just sit it on a concrete block? I have dug down a foot and will back fill with the same material as the shed is sitting on. The block will sit on the compacted stone. The connection to the shed will be a 2 by 6 nailed to the outside of the shed wall, with 2 by 6 2 feet on center. I figure if the shed moves with the frost then the canopy will also. What do you think? Footings or a block?