Gilbert Fritz wrote:
Earthbag would need buttresses. Rammed earth needs forms. Cob can go slow and mold in a damp cold period. I am not sure on the process for slipform adobe.
All of these techniques will behave about the same in terms of the need for buttresses, to my knowledge. That is, for the same thickness and taper, earthbags aren't going to need buttressing and adobes not need it. So speed is your real issue.
It seems like the carpentry involved in formwork might be intimidating you- is that an accurate impression?
I can't claim to have built with all four of the styles you mentioned, but I gather that cob is the slowest. Making adobes now, in the fourth week of September, and waiting a couple weeks for them to dry before you build with them... that's probably too slow for you too.
So earthbag or rammed earth? I hear that earthbag is faster. Have you sourced some bags?