Welcome to Permies. I would love to help you, but your question at this point is too nebulous to really allow good guidance. The land, your location, materials at hand, clay type, your skill sets, and the list goes on. I would recommend going back through and reading all you can that is on this sight about Cobb, and anything else you can find. Then do a design that fits you land and location. From that point, we can give you help on the particulars of you project. I feel bad that I haven't answered you more directly, but I believe I given you the best advice at this stage in your project. Let me know if you think I could have done better.
Sorry. Well let's say it's gonna be a square house. The land is in Stone County, Arkansas. Idk how I can explain the kind of clay. It's a redish brown. It's very humid in this area. I have very little experience with cob. I've read a WHOLE LOT on it tho.
I know one person that built a two-story, but it was a hybrid--cob first floor and strawbale upper. They used 3-4 foot thick buttresses for load bearing floor supports IIRC. They said that if to do it over they would have done timberframe with strawbale or waddle and daub infill.
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