Well, there is Slab, Stem (pony) Wall, Rubble trench, pier and beam, Basement, and Gabbion; or any combination there of. Take your pick. Not all of them require loads of concrete. What it really boils down to is what is your soil, how much weight does the foundation need to support, and where is the freeze line?
I would first identify my soil type and depth. The deeper the soil to bedrock the more Potential there is for movement. The less sand in the soil as general rule, the more resistant it is to weight displacement. Is there expansive clay? Does the moisture content remain fairly stable or does it heave a lot through the seasons?
Next would be to calculate the load of the entire structure, including contents and occupants. Does it require a deep or wide foundation? Does it need to be reinforced to address stresses?
How deep does the frostline dictate the perimeter be?
Where are you building? How big do you want the structure to be?
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