I was watching This Old House the other day and they were using a new footing that didn't require digging down below the frost line in Mass, where it is typically 48". It is on the video at the link at around 5 minutes. https://www.thisoldhouse.com/watch/newton-gennext-all-decked-out Around here our footings only need to be 12" for most structures assuming you land on undisturbed earth. If you're on fill it can be a lot deeper. Has anyone seen these in use in real life? Looks like a neat concept.