EarthKaya Update

Earthbag building in South Africa
Earthbag building in South Africa

“EarthKaya is dedicated in providing low cost, low impact, earthbag building solutions in South Africa. Less time, less impact, less cost.

In a world where organic is more expensive than traditional crops, solar panels are often costly to install and electric cars inconvenient to run, many people may be reluctant to ‘go green’ at home.

But imagine a process of home building that is more economical than traditional methods, equally as sound structurally, well-insulated, sound-absorbent, releases less CO2 emissions than brick homes and reduces the carbon footprint by 70%.

EarthKaya does just that by creating structures using locally produced earthbags which are coated with small amounts of cement or optionally an environmentally-friendly plaster such as adobe or special lime after building.

Earthbag homes are resistant to wind, sun and water vapour, remain cool in summer and warm in winter, are non-corrosive and rot-free, meaning no pesky termite problems.”

Read more at the source: Earth Kaya
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15 thoughts on “EarthKaya Update”

  1. Hi,

    The most attractive features that makes think that this is an improved system are:

    1. no barb wire.
    2. not having to keep bag open on wall, instead just complete by dumping material into open channel and tamping.

    These features free up so so much work.


  2. If Noel’s 8 point list of advantages are all true, then they are excellent points.

    I recognize that those items MIGHT be true in theory, but I’m not convinced they are actually true in reality.

    Noel’s point 2: All of the wall material must be hauled up the wall in both system. Whether it’s in a prefilled bag, or in buckets really doesn’t matter. It all has to get hauled up there to get the wall built. If you have the same number of helpers filling buckets and hauling them up the wall in a standard earthbag system as you have helpers prefilling filling these double tube bags, I predict that the tube bagging will go slower. However, if someone has done some side by side timed testing to see which system moves faster at building a wall, I’d be interested to see their experimental data.

    Point 3: I see nothing about this system that makes it need any less buttressing than standard earthbagging. If Dr. Anderson built long straight walls as part of his design, and did NOT have those interior partition walls ACTING AS BUTTRESSES, he would need to add buttresses.

    Point 4: This system MIGHT make for easy bond beam creation, but I never thought creating bond beams was particularly difficult in the first place. However, assuming that this style bag is a drastic improvement in the creation of a bond beam, why not only sew up these double tubed bags for the top layer of bags and use regular bags for the rest of the wall?

    Point 5: The uniformity of these bags isn’t necessarily any better than the uniformity of a standard bag. As long as a builder is using bags of all the same size of whatever style, bag uniformity is more a function of consistent filling, laying practices, and consistent tamping. I have no doubt that someone that has sloppy practices can make these double tube bags be just as sloppy as any other bag. I congratulate Dr. Anderson on training his work crews to pay attention to details and perform consistent quality work. In my opinion, that is probably more important than the bag style.

    Point 6: Maybe less plastering. Maybe not. Again, I believe consistent detailed work in filling/placing/tamping bags is the biggest factor in reducing plaster work. This is another area where I would love to see someone’s experimental data in a side by side comparison with standard earthbags.

    I’m very open to reading a link, if anyone has it, where timed side by side comparisons have been made between this system and standard bags. It would be particularly important to have the crews that build each system have similar training and experience. Perhaps such a link might convince me of these claims. As of now, I’m skeptical of those claims until I see some data proving the accuracy of those claims.

    • I’d guess both are comparable in terms of labor and speed of construction. Maybe Dr. Anderton or someone else has performed timed tests, not sure. But this type of building is efficient. A large school built this way is the first photo in my book. It’s an amazing photo you have to see to believe. It’s a large school with a magnificent sky above. This system is catching on and gaining publicity (he’s won at least one award).

  3. Hi,
    I think the bags have great potential because of the following points.
    1. with this system you will not use barb wire and the associated labor needed to install the barb wire. Barb wire can be very troublesome.
    2. you can prefill and lay the bags without too much handling time on the wall. Less bulky maneuvering on the wall and bucketing up fill material.
    3. Dr. Anderson’s buildings don’t seem to use buttresting.
    4. Easy lintel and bond beam creation.
    5. More uniform bags for greater plumbing and leveling.
    6. Possible less plastering.
    7. innovative floor stabilizing.
    8. possibility to use leno bags for greater grab.

    If this system makes earthbag building faster and labor costs lower any cost associated with the sewing is greatly offsetted.

    thank you.

    • Good points. It’s a good option worth considering. The sewing shouldn’t cost a lot if you can track down the right person. Look for a seamstress who works from home rather than a commercial business.

  4. Hey Owen,
    Do you know of a source for this type of tubes? Didn’t see anything on eternally solar.
    I assume the cost and labor rise a good bit, but could present a better option than frequent butressing in the desert.

    • Yes, South Africa has deserts and yes they have building codes. That explains why this building method was created. Dr. Anderton took a basic concept (building with bags) and evolved it to meet his local situation. Quite a few of our readers live in similar places with no clay.

  5. I hear you.

    I agree with you.

    The problem is… I’ve seen the tin shack slums in Soweto. None of those structures is built according to building code.

    Poverty is very real there. Apartheid was a very effective tool to keep the poor of South Africa as poor as possible. Economic recovery from that oppression is going to take a long time.

    The poor people there deserve the chance to build quality housing for themselves without spending a fortune that they don’t have. Most of these poor are hard working resourceful people. They simply need a chance to build a life for themselves.

    Progress after Apartheid is real, but progress has also been very slow.

    The time has come to empower the poor to TAKE CARE OF THEMSELVES.

    Government regulation in the form of building codes only serves to keep poor people in those tin shacks.

    I call that a tragedy.

    Let them build their own quality home. The more simple the system for building it the better. Let them build on land where they can grow their own food to feed themselves.

    Just one problem. The poor have no land that is their own. Nobody can afford it.

    • Sure, but Dr. Anderton is just developing one more option. It’s not necessarily the lowest cost option or the best option for everybody. It’s for people in deserts. And keep in mind if you stack regular size earthbags full of sand the walls will fall over. Walls made entirely of sand bags are unstable (unless you add special buttresses, etc).

  6. I really don’t see the point.

    I looked through the Kaya website, and they are simply filling the outer tubes with earth or sand, and the center channel with earth. Dr. Anderton mentions that filling with insulation is a possibility, but he also makes it clear that is NOT what they are doing in South Africa.

    Why bother with that?

    I can see using this system if you are going to be filling the outer tube with insulative material. Then there is an advantage to the system.

    If you are going to fill all those tiny tubes with earth or sand anyway, it would be a lot easier to construct a building using simple bags.

    There really is no reason to COMPLICATE a very effective simple system, unless there are commensurate benefits to be gained from the added complexity.

    Dr. Anderton mentions that sand has some insulation capacity, and well… yeah… A LITTLE. However, that is a huge stretch. It’s a slightly better insulator than earth… ONLY IF THE SAND IS DRY. Even then, we’re talking about very small R factor for that tiny outer tube if it is filled with DRY sand.

    The only way this system makes any sense is if the outer tube is filled with scoria, pumice, vermiculite, papercrete, heck… even filling the outer tube with empty plastic soda bottles would be DRASTICALLY better than filling with sand… at least when it comes to insulation.

    Dr. Anderton also talks about “standardizing” earthbag building so that he can get it in building codes.

    That sounds to me like a foolish agenda. It’s as if he wants to over complicate earthbags so that he can get code approval. I guess if he makes the process expensive enough, only then will governments approve it?

    A far better solution would be to simply get rid of most of the building codes… of course, that solution makes way too much sense, so governments are very unlikely to do that.

    Seems to me that earthbag building has been standardized for quite a few years already. Sure there are some variations on the standard techniques, but the standard is well established and understood.

    If someone DOES fill the outer tube with insulative material, there is a very strong likelihood that the different fill materials will compress at different rates as it gets tamped in place. This sounds to me like a system that would be exceedingly difficult to tamp evenly. It’s very likely that many walls will be very prone to leaning inward or outward as they go up because of the different compression rates of the differing materials when insulation is used.

    Seems to me it would be FAR simpler, and perform much better, to just use a standard earthbags and fill them with scoria entirely. Problems solved, and construction could proceed at a much faster pace using a much simpler system. Use mesh inside and out, tied through the wall, with plaster, and you have a very strong insulating wall.


    The simple solutions are usually the best ones.

    • Briefly, this method evolved in Africa where sand is abundant and clay is lacking. It provides one more way of doing things. Regular earthbags will work fine for most.

      Dr. Anderton is trying to work within the existing system to bring about change. Others like me say the system is broken and recommend moving to rural areas with few or no codes. But I can’t tell people what to do. Everyone has to find their own path in life.

      Build a test wall and/or small shed, etc. when experimenting with any new building technique. This is a great way to learn. Work out the kinks before building something large and complicated.

  7. Notice the small bags they’re using to plug the ends of the middle channels. They contain the rammed earth so it doesn’t spill out during construction.

  8. We’re always looking for lower cost building methods. If you have experience using this method with tamped earth in the middle then please contact me by email or leave a comment.

    My hunch at the moment: concrete is needed for maximum strength and to meet code. Tamped earth will probably suffice on simple structures in non-code areas.

    There you have it. Another exclusive breaking news story at Natural Building Blog! We’re more than just a bunch of pretty pictures.

  9. It looks like they’re filling the inner portion with tamped earth. Most bags of this type are filled with concrete. Search our blog for Eternally Solar for more info. They’re pioneering this method in South Africa.

    Quick recap for those new to this method:
    – these are special made earthbags with a tube down each side
    – they’re mostly used in deserts where clayey soil is not available
    – the tubes are pre-filled with sand
    – one or both tubes could be filled with insulating material such as perlite or scoria in cold climates
    – the inner part between the tubes is usually filled with concrete to stiffen the wall
    – our blog has free drawings and all other details thanks to the generosity of Dr. Anderton who invented this method
    – this method has been engineered and tested for code approval in South Africa
    – you can make your own bags if you have a heavy duty sewing machine or know someone in your area who has one
    – Dr. Anderton has kindly granted permission for owner builders to build their home this way (contact him if you’re planning to start building commercially)


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