I have purchased a Compressed Earth Block (CEB) press after a lot of research. This summer I will be building a barn with CEB's as a proof of concept, so that maybe I can build a house out of it in the coming years. I am going to put several sensors inside/outside to test how it performs, and also how well it holds up to the weather elements. I live in southwest Virginia, a few minutes from the Blue Ridge Parkway. My family will be setting up a small little farm on 5.5 acres and this barn represents the first step in that process. I don't have to worry about building codes since the barn will be 900 sq/ft and classified in county documents as farm use.
Leading up to my build for this summer I'm starting to source materials; Subsoil, Lime, Cement. The table below gives an idea of where my research has led me in terms of percentages for the CEB material. I know there are mixed opinions on what the correct percentages of each item should be, but this is what I'm settling with unless I hear a good case otherwise (the % table is below). All values listed below are 20% more of what I need to make the blocks & mortar, I'm figuring waste so I don't come up short on any given product. I'm using 2 different stabilizers that work extremely well together only because I want to reduce my usage of cement without eliminating it completely. Moisture content will be roughly 10% when I'm mixing and pressing the blocks. What I'm here to ask about is Lime, Concrete & Subsoil (Clay/Sand/Silt/Fine Gravel).
Subsoil: I can't use the subsoil on my property, way too much clay and large rocks/boulders to contend with, excavation would be costly. The neighbor landscaped/graded his lawn and ended up spending a fortune, I'm not going that route. With that said, I need to purchase Subsoil from around where I'm at, as locally as possible. What type of company would I contact to get a quote? I'm looking to buy roughly 29 cubic yards (Clay + Sand + Fine Gravel), more is fine if it needs rounded off for a truck load. What type of questions do I ask so I make sure I get what I want, i.e. no topsoil, no organic material....etc.
Lime: This area is probably my least understood material in the process. Some use Agricultural Lime (hydrated lime is readily available), others Reject Lime (whatever that is). I've searched each term and very little is talked about in reference to CEB's, at least as to what type of lime they use. I know of a local quarry about an hour away from me but before I call what do I ask for?
Concrete: Still in powder (dry) form when delivered. Do I buy it by the bag or get my ready mix supplier to deliver some? What composition do I ask for? Should I ask for specific ingredients? Volcanic Ash, etc... It's only about 2 cubic yards I need.
Concrete & Lime onsite Storage: My concern, it will get wet from rain potentially (probably) before I use all of it. Even a canopy wouldn't do, we can have good thunderstorms at times where the rain comes in from the sides. So am I going to have to use a tarp in those conditions directly on it? And wind, I don't want it to fly away. I also don't want ground moisture being drawn upward into the piles and then when I get to the bottom I have an impossible mess to deal with. Once again, maybe a tarp to put each product on and a tarp to cover it with stakes at each corner and only uncover when I need to draw from the pile. Better plan anyone?
All these problems didn't occur to me until I started to build everything in my head and on paper. Now that I have a CEB Press I need to get things in action. I'd like to have my bill of materials by the end of this month so I don't run into any situation where it might take a while to get a product sourced or located.
That's a big question, so if I don't remember every part just ask again.
Subsoil- Excavation companies that dig out for foundations etc. usually have extra fill available at a small price, but this is not going to be graded, so you will still have to process the material. There's a lot to this part, depending on the soil and what the stratification test shows. The modifiers added to the soil will vary according to soil type, so we need the soil tests before final acquisition of materials.
Lime- Hydrated lime is best and can be purchased inexpensively.
Concrete- Concrete is a cementitious mixture typically utilizing Portland Cement as the "glue" for the aggregate. You just want the Portland Cement, in powder form with nothing else added.
On-Site Storage- I typically buy these goods on a pallet, either in 50-80lb paper bags or 1 or 2,000 lb super bags. I save the plastic covers from the pallets of wood pellets that I heat my house with in order to cover these kinds of things. The other materials are typically stored on the ground loosely covered, but hydration ratios must be adapted to the amount of water absorbed by the sand and clay. A bulking test can tell you quickly about how much moisture is present, or just know your mix.