I don't have an
answer for your question. People don't seem to like to talk about earthships around here much.
Before you decide to build an earthship, you might want to find a place to make a small retaining wall from pounding tires full of dirt.
Mike Reynolds used heavy equipment to dig the dirt that was used in the tires. If you plan to dig the dirt by hand and pound it in the tires....you may find that YOU are the tired one.
I made a small retaining wall in my
yard from dirt that i dug up and wheel barrow-ed over and pounded... 4 tires was
enough for me. Not 4 layers - 4 tires
side by side. Going up to higher levels without machines would add even more hard labor.
I may still use pounded tires as a footing for my next structure, but I'll probably use other materials for the walls.