Mike G wrote:As for "looks sturdy". Well, yes, it is, but try this experiment. Go and hold a sheet of ply vertically in a stiff wind.
Who needs to do this experiment ? It is well known that a stiff wind is
always invoked when you begin to manhandle sheet goods outdoors
I thought it was not likely to be a miscalculation.
My dad has a fairly large cedar greenhouse. When it was new he and my mother spend a windy evening serving as ballast to stop it blowing away, after which it got an angle iron frame added in the middle, and a circuit of 3" heating pipes which were arranged to weight it down rather. It's still there after 50 or 60 years, so it did the job !