Open source brick machine: the evolution

Tristan sez, "Open Source Ecology is a social enterprise based in Missouri. We develop open source machines that can be made for a fraction of commercial costs, and share our designs on the Internet for free. We've just designed version 4.0 of our compressed earth brick press, the Liberator. With this machine, anyone can make solid, 'dirt cheap' structures from the earth beneath their feet. This linked video shows the evolution of the CEB press from 2007-2012."

The CEB Story 2012 (Thanks, Tristan)



  1. Interesting machine, I have only 3 critiques:1. What are the seismic properties of the range of bricks it generates? There are plenty of places where freestanding brick structures are inappropriate.
    2. For a developed economy, it’s a slightly redundant technology that has to compete on price & quality against idling brick factories and a global supply chain.3. For a developing economy, this device may be too dependent on that global supply chain for parts, and may be too expensive still. I look forward to the version 5 or 6 that’ll work in rural Asia and Africa at “Barefoot College” prices.

    1. Bricks have to conform to the ASTM D1633-00 stabilization standard requring 4-hour submersion in water and then withstand a minimum of 300 psi. This is a higher standard than for adobe which is required to withstand 300 psi on average.

      A press can produce up to 720 bricks per hour (one every 5 seconds). A brick in developed countries usually goes by about $1 per brick. If a backhoe is available then it can be operated by 2-3 persons. You would have to incur more than $720/h in labor and equipment cost to make the press economically unfeasible. That’s unlikely.

      The advantages of on-site production of bricks are reduced transport cost, reduced cost from waiting times for bricks. The bricks themselves provide better heat isolation than hollow bricks or clay bricks. They are more sound damping than most other brick walls. They need no or very little drying once pressed. Unlike industrial bricks they do not release chemical fumes requiring extensive fuming out times of the property before levels drop to nontoxic concentrations. Unlike fired clay bricks and other low-cost brick production techniques the method produces bricks with true 90 degree angles and all bricks are of uniform size. The bricks are fireproof. There are clear advantages even in developed countries.

      1. Sounds like an ideal technology for post-war reconstruction. Should share with Iraq, Afghanistan, Sri Lanka, Libya, the West Bank, and Syria after some kind of peace is restored.

  2. I can definitely see the appeal for low impact development with this type of device, but the above critique is fair with respect to cost and simplicity.  If you could make this work without a hydraulic press, no electronics, without any welding, and with as little steel as possible, you’d be on your way in developing countries.  A great start, though.

  3.  I’m not quite sure about this, but I think there must be a reason why bricks these days are not made from compressed soil, nor from clay (although that used to be the regular thing) but from sand and limestone, and why they are burnt, not pressed.

    I’m also not quite sure what types of material there are in the soil being used and whether those will stay as they are in the brick, especially since the bricks aren’t even completely dry when they use them. This is something that may show in a finished building a few years into service: Will there be cracks, will the material settle?

    And third: I’d really like to know some data for these bricks in comparison to industry-made ones: Which load can they bear, which load can they bear per kilogram of their own mass (equivalent to how high you can stack them), how well do they conduct heat? I’d imagine that they’re a fair bit behind industry products.

    All that said: I’d imagine that this thing could be a hit in countries/societies where people have much more time than money, or where labour is very cheap. Not for huge buildings but simple homes for people who could otherwise not afford one.


      These guys are right down the road from me.  They use clay and sand they dig next to their plant, extrude and cut it, and fire the bricks in kilns. 

      I would imagine that pressed earth bricks are not going to be particularly waterproof, although if built on a foundation of rock or gravel, with good drainage and a good roof overhead, they will probably last almost forever.  When you’re wondering if you’re going to freeze to death next winter, or be eaten by bugs and animals next summer, ISO standards probably aren’t the top thing on your list.  The point isn’t to compete with commercially mass-produced bricks.  The point is to allow people to produce their own bricks for housing using whatever they have available for power and material on the spot.  And from what I’ve seen, coming up with some scrap metal – ship/car/truck/train sheet metal, drive shafts, etc – isn’t too difficult in most places. 

  4. I wonder what qualities the earth has to have to make suitable bricks (relative amount of clay, sand, loam, gravel; alcalinity; any other properties that might be relevant)

    A wonderful machine, at any rate.

  5. *sigh* CEB has some great properties, but I really wish people wouldn’t call it a brick.  It produces brick like shapes or even things shaped much like cinder blocks, but they are not the same.

    My main issue with CEB is the fact it is not water proof, while a fired clay brick is.  That’s not to say if you built a structure out of CEB that it would fall apart or deteriorate (obviously you need the right exterior just like any structure).  But you can not use CEBs when doing below ground work.  Obviously in some parts of the country that’s not a problem, but where I live most of the houses/structures have some type of below ground foundation.

    And as mentioned above CEB technology has been around for decades.  Manual presses aren’t complicated, but the addition of hydraulics yields much higher compression forces even if it is a hand operated pump.  The addition of some concrete to the mix also seems to help stability.

    This is a good place to start:

    If I had the time I’d probably build a semi manual press, I do have a lot of uses for blocks around the yard.

  6.  I think it’s clear that this is a machine intended for developed countries only. In the third world, they use this: It’s hand-cranked, just as fast, only has a couple moving parts, and is forged from a bit of scrap metal by the look of it.

    This kind of cheap machines have been used for at least a decade; I remember seeing a documentary about it a while ago. The great thing about this method for a poor village, is that it’s completely auto-sufficient. You don’t need to pay for any materials or skills from the outside, and you get one of the things you need the most. In the documentary, an ngo was bringing them the machine and getting them started, but the video I linked shows this isn’t necessary.

    Now, I don’t want to be harsh to the “liberator”, but it certainly isn’t the “first open-source brick machine” (the ngo was obviously doing that). I guess it’s possible that it would get “huge adoption very soon”, but it would be in countries where muscle power is more expensive than machine power.

  7. It’d be interesting to see if this could be modified to produce interlocking bricks. In development projects I’ve seen in poor rural areas, cement holding the walls together is by far the biggest cost for building schools and houses, while brick presses/handformed earth bricks are fairly easy to come by.

    Adding cement to the earth mix a) waterproofs them and b) means you can create shapes that don’t require more cement to hold them together, except on a layer or two at the top and bottom of a wall. Although you’re still putting cement in the mix to toughen the bricks, overall you use less.

    The downside is that at the moment, this requires hydroforming – ie. use of water in the shaping process. Which can be a scare resource depending on where you are.

    Might be that the press is already capable of this – but the video link isn’t working for me.

    1. I suspect that the tensile strength of these bricks is not sufficient for this purpose. Making them in interlocking shapes would just give you the *idea* that they might hold each other together when, in fact, they wouldn’t. 

    1.  i seen a construction method similar to that from the dark ages, but it used reeds to make the outer structure of the wall (the reeds were woven around posts kinda like wicker) then a mixture of mud and dung were mixed with straw and packed into the walls to fill the gaps.
      found it, its called “wattle and daub” construction. seems kinda similar.

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