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Wood frame, sawdust concrete, wofati inspired building

 
pollinator
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https://www.motherearthnews.com/green-homes/building-a-sawdust-concrete-home-zmaz78jfzgoe
"Here is the mix he used: one part of cement, one part of diatomaceous earth, three parts of sawdust, three parts of shavings, and one part of clay . . . all volume measurements. Since sawdust-concrete has a higher absorption rate than straight concrete, Friberg added one part of clay to the mix."

I want to put up a building. I'm really loving the wofati but I don't have heavy equipment or a gaggle of helpers. I do have some woods that need thinned and amish neighbors with sawmills. So here I end up with this blend of ideas. I can get some help clearing the woods and putting up the frame. Hoping that I could set up a frame between the posts and pour the sawdust cement in, then move it up and do another layer, kind of like how ya do cobwood building. But just doing a board on each side and building up the layers as I can. I'm not entirely sure that makes sense so I'll try to doodle a picture.
~Masonry cement 75# bag for $10
~Diatomatious earth 40# $?
~sawdust possibly free
~clay soil, free
~reused billboard tarp liner 14'x23' $30 each plus shipping

I'm thinking I'll see if I can throw together a brick form with some scrap wood. I have some DE around and I could try out mixing some up and see how it goes. I can always find use for bricks!
As to the building.. I'm not sure how big it'll be yet. Maybe tiny house size-ish. It'd be great to be big enough I could more or less live in it.

~Posts in
~Frame raised floor, fill gravel then sand
~Frame roof, sawdust concrete
~Sawdust concrete floor
~Frame base of walls, first layer sawdust concrete
~When set remove frame, frame just above the first layer and add second layer. If I have something like 2x6 boards for the frame to pour the concrete into then the layers should go fairly quick to make.
~Continue layers up walls, leaving framed door and windows
~Now that the walls and roof are in cover with tarp liner.
Here is where I need to go away from the usual wofati idea. I don't have machinery and I don't have fill dirt. I do have.. Sawdust. Junk hay (moldy, etc). Branches (woods thinning). Wood chips (woods thinning). Barn cleanout (myself and neighbor). So I'm thinking once I get it covered with the tarp liner I can add as much as I can to fill in over time. The first year I would try to get as much cover on it as possible. Over time it would take on the more covered hobbit hill look.

This has been percolating but not too long so feel free to point out possible issues! Especially the more knowledgeable, experienced builders. Thanks!
 
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We used sawdustcrete in our chicken barn, and it lasted for 27 consecutive years so I know first hand that it is durable.

As for fill, wood is just minerals pulled from the soil, and when it rots it goes back to being soil. IF the WOFATI was adequately protected from rot, it may be possible to use wood chips around the building instead of soil. A person would have to constantly add more as the chips decomposed, but if you got to be REALLY good friends with an owner of a tree trimming business, it might work.

I have not had enough coffee yet, so my ideas may be slow in coming, but I might be concerned with the smell of the wood chips decomposing and coming through into the house, but suffering snot balls that would be a warm house. Nothing insulates like wood chips or sawdust!

As for a design, I am sure you got one that is great, but I drew up a small 24 x 24 WOFATI that had managed to get natural light into every room of the home, including the bathroom. It had only one door in the back so that I got the most earth protection, but I put a door in for light, and for egress safety.
 
kadence blevins
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I realized I had the perfect test site! There is a little 'room' of the barn that I had some rabbits set up in a colony for a while then some chickens. I believe I had a rat stealing newborn rabbits. Then a mink or something got in when I had the chickens and ate them. So with a cleanout, new door, some repair, and a sawdust-soil-concrete floor.. I think it would be perfect to try rabbit colony again. And that's been on my to-do list a while.
It's on a slant so I'd need to do some filling in.. Make a form for the floor.. Mix it up and pour the floor. The floor would have some small drainage holes poked in it so the bedding doesn't get soaked.
One bag cement, one bag DE, three feedbags sawdust, three feedbags soil. I'm not sure how to do it by volume parts unless I do it by scoops with a #10 can...
I've been looking at sawdust concrete and soil concrete and everyone does it a little different so this seems workable. It's not like I'm parking vehicles on it lol. One adult human will probably be the biggest thing on it. I think the area is 9x10ft I'll have to measure. I'm not sure if I'd double it if that would be enough...? Three inch thick?
I understand how concrete works but don't have first hand experience and the only person I could ask is one of those 'nope not worth it' types that would want to take over and do the project their way.. IE not how I want it at all.. So I defer my thoughts to you all and multitudes of articles and videos.
 
Travis Johnson
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In making concrete, sawdust create, earthcrete, etc...most people do the proportions by "the shovelful." But with ratios it does not matter if it is by the teaspoon, or by the truckloads, the portions will be the same. Just make sure you use the same size for everything uou add (2 teaspoons of cement to 2 truckloads of sawdust would not work), and do not forget how many of each you add.
 
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