Ferrocement https://milkwood.net/2010/11/08/how-to-make-ferrocement-garden-beds/ I think this could be my method and medium. I found a ferrocement forum and website https://ferrocement.net/ which has some good articles on ferrocement. The forum will help wiht my particular questions i guess. I'm not sure wobbly curvie is really my style but i do love Gaudi the Spanish architect and i've seen some wonderful ferrocement houses. I just didn't know it was called ferrocement and I didn't understand the difference between that and concrete construction. Ferrocement is fairly cheap i gather but very hard labour. It does not use formwork that is typical of concrete construction so that makes it cheaper and easier. I"ve got a number of small projects to work with before trying to build my bedroom. I want to make flagstones, a retaining wall, those garden walls look worth a try, there's the dam project at hte bottom of the block to catch the runoff and so on. There's a couple of inspiring houses that you can see on the net in ferrocement - steve kornher i think and probably timolandia - tim sullivan. These people are in a book i am looking at called handbuilt shelters. https://matahina.blogspot.com/2010/04/timolandia.html https://www.flyingconcrete.com/index.htm Looks like its not good for a flat roof though.