I think for a lot of homesteaders and builders, even in use around WOFATI's; Earthcrete has its place, and I feel so strongly about that, that when I did my classes on sheep farming, I mentioned Earthcrete.
Earthcrete is using the existing soil, then mixing it with Portland cement, and then mixing in water and letting it harden. It can be mixed in a cement mixer too, but the greatest advantage of Earthcrete is in vast slabs. That is because it is so easy and cheap to make. A cement mixer is not even required!
All you do is take a rototiller and till up the soil to a consistent depth, say 4 or 6 inches. Then calculate how many bags of Portland cement you need to make an earthcrete slab that size and depth. I use 5 bags of Portland cement per cubic yard (27 cubic feet) of earthcrete. Spread the cement powder out as even as you can, and then rototill again until the earth/cement is consistently mixed. Now using a hose or buckets of water, add in the appropriate amount of water, and mix again with the rotortiller. After that, the earthcrete is troweled and finished just like you do any other concrete project. And by the way, if you do not have a rototiller, they can be rented for a project like this.
Another method of using low energy earthcrete or concrete is to make Bagcrete.
This is like cheap concrete blocks. All you do is mix earth or gravel with Portland cement, and then use that dry mix to fill paper bags.
These you just stack up, say around a culvert pipe, or as a retaining wall, and then let nature do its work. As moisture gets into the mixture, it hardens into an earthcrete or concrete block. The paper then disintegrates on its own, or if you do not like the slowness of that, just burn the paper after it hardens.
This has a lot of use around a WOFATI build because it is a great way to make retaining walls, or other verticle structures where form-building would take extra time and materials.
A cement mixer is easier to use, but in a pinch a rotortiller could also be used to do the mixing on the ground, then the mixed soil and cement shoveled into the paper bags, or sandbags...
But if you do not have a gravel, or want lightweight concrete do not despair. My Grandfather needed concrete flooring on an old timber framed barn for his 50,000 broiler chickens, so he used sawdust as the medium instead of gravel in the mix. The floors held up for 27 years of scrapping by tractor every 6 weeks. It was waterproof, smooth, and light weight!
But there is a caution here, concrete is not as heavy as people think. Yes, it is 3000 pounds per cubic yard, but I did the calculations on my concrete countertops and a square foot of 2-inch-thick concrete countertop is only 12 pounds. A wooden kitchen cabinet is MORE than able to hold that little bit of weight up.
In fact people often think of granite has being "heavy" and aluminum as being "light", but did you know a cubic foot of those two materials has the exact same weight? I mention this to show that perception can get in the way of sound building practices sometimes. More than once I heard, "I hope you made your kitchen cabinets extra strong to hold the weight of that concrete!" I did not use sawcrete on my kitchen cabinets, but used real concrete derived from gravel.
Ok I got distracted this summer with a lot of other projects. So at the moment we’re still living in our work shop. This winter I’ll sit down, come up with a final plan. Also I’m getting my logging operation off the ground so logs or not going to be. Problem. Thanks all for your input I’ll keep you posted on design and such looking forward to more feed back. It’s been a busy time but it’s finally time to get this rocking. My wife and I beleave this build has a huge return in investment as the house will take care of us and in the long run be worth the effort of the build.
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