Here’s a breaking news update from Brazil. We owe a big thanks to Paula, one of our readers who tracked down these details, and to Andre Ferreira and Fernando Pacheco, who are building with hyperadobe in Brazil for this latest update.
Andre Ferreira said that he has already built a rounded house using hyperadobe but not a dome, and that he doesn’t know about any domes built with this technique. He built this house after seeing photos of the technique and without taking any courses. [Ed.: This is what I’ve been saying. Do the basic research and then build a small test structure. You don’t need to spend a fortune on training.]
He bought the bags from Citropack. And there you can see the difference between the meshes. The image telapreta50 (shown above) is the one used in hyperadobe in Brazil. And here you can see the difference between the fruits and veggies bags.
He said that Citropack is not making these bags if it is not for a big order. Andre doesn’t know about anybody else that uses this technique in his region (Espirito Santo) apart from Fernando Pacheco. [Ed.: The photo above confirms they are using the same type of bags we have been discussing lately. That means there are plenty of other mesh bag and tube suppliers.]
Fernando Soneghet Pacheco, the original developer of hyperadobe, said he has improved the superadobe technique because after having done a course he realized that there were a few problems. The hyperadobe bag or tube is narrower, so it needs less soil and it’s cheaper. And you can also save money with doors and windows bucks (rough frames) as they don’t need to be so wide. The mesh of hyperadobe bags help for stability and remove the use of barbed wire. Also, plaster bonds more readily to the mesh.
Fernando said he hasn’t built many structures himself using hyperadobe, but he knows that his students have built all around Brazil. It has been 5 years that he has developed this technique so he imagines that it has probably spread quite a lot, even though he is not aware of it in other countries. He has a little book about hyperadobe but it hasn’t been published yet. The bag from Citropack has been developed with his help. He thinks that 35cm wide for the bag is the best after the tests he has done. He thinks domes with less curvature (steeper sides) could work with no problems.
Thanks again to Paula, Andre and Fernando for sharing and caring. Because of the large and growing interest in earthbag building, these types of improvements will likely help hundreds or even thousands build more efficiently. And as the scale continues to tip in favor of this building method, it will likely grow much faster.
just to throw this out there,instead of using barb wire if you thought you needed it to keep the wall from shifting,could you use dried corn cob husk every so often.( every other one facing the opposite direction to kind of lock the wall from shifting,) being the cobs taper. scott m
Barbed wire is much stronger than corn cobs and also provides tensile strength. This is very important in seismic and hurricane areas. Less so in small structures in areas with no earthquakes or hurricanes. Barbed wire is critical in domes to prevent outward thrust. You have to decide what’s most appropriate for your situation.
On the citropak page, here is a link that works, but I haven’t checked what their shipping options were outside of Brasil:
http://www.citropack.com.br/biopack-hiperadobe.html
The links to the mesh bag suppliers & to Citropack are both broken. I googled it but was unable to find anyone offering mesh tubes. In looking at bags, is there a certain type I need, and what size is recommended? Is there a supplier most people are ordering from that I dont know about?
There are lots of mesh bag suppliers. They’re used for many purposes. Try different search terms like ‘raschel mesh bags’.
Previous blog posts describe everything you need in great detail. Search this blog more.
Here are some suppliers:
Syfilco http://www.syfilco.on.ca/erosion.html
Bag Supplies Canada http://bagsupplies.ca/index.php?page=tubenettingrolls&loc=canada//
If you consider the price of the raschel tubular bags and difficulties to get the suppliers today, would you agree it isn’t that cheap to build hyperadobe?
It depends on various factors; for instance, since hyperadobe may not need barbed wire reinforcement, or plaster mesh, this could make a difference in comparative costs.
Thank you for this wonderful blog, I bought your book yesterday and am getting hooked on building with regular earth bags or hyperadobe, however after watching the decay of the domes in the philippines I have a few questions. I plan to build a roundhouse with straw/hay roofing it is to be located in the philippines and I plan to use lime plaster inside and outside. Now I worry about a plant or other greens all of a sudden growing out of the walls. How can I be sure that this will not happen? also If I made a tamped earth floor would it make sense to add a small amount of cement of make it more durable? Thank you in advance
I doubt anything will grow out of lime plaster. It has natural anti-microbial/fungi properties.
You’re talking about thatch roofing. That’s the correct term so you can research this in more detail.
Yes, you could add some cement to the floor. That’s called soil cement. You can get the details online. Use a waterproof barrier under the floor such as 6 mil plastic.
I was wondering if it would be possible to lay tandem courses? Say you did the outside layer with the 70/30 sand/clay mix, and simultaneously erected an inner course filled with the insulator material…I would think the soil based mixture would also spread horizontally partway into the insulating layer to hold the vertical bond, but I am no engineer, just a design student. Any thoughts?
I live in Wisconsin and need the insulating layer, but I like the thermal mass and its flood resistant properties.
I was also curious if one could work certain organic matter into the soil mixture to help with pest control, like Citronella, Beebalm, or Marigold; or if you could do the same thing with antiseptic and anti microbial plants? Here I would think they would just naturally compost into the soil mixture after time.
Do any of these type of structures have issues with mold?
Double wythe walls (two walls built next to each other) greatly increase labor and cost. The most efficient methods for earthbag buildings in cold climates are discussed here: http://www.instructables.com/id/How-to-Build-an-Insulated-Earthbag-House/
It’s best to add insulation on the outside of mass. Add insulation to the outside of the earthbags so the mass will help stabilize indoor temperatures.
Borax is one of the most effective additives for pest control.
There’s no risk of mold from compacted soil if there’s adequate ventilation for drying the walls. For the rest of the house, don’t use materials that can mold.
Thank you so much for your’s answers.
When you refer to columns, do you mean that I need structural strenght for the house? Because it’s so big? I choose this method, with earthbags because I understend it’s no need for structural strenght and can be done by nonprofesional person, like me. I plane to do this all by myself!
And I read about materials like slag or perlite are radioactive. What do you think about?
Every building needs structural strength. I suggest you do more research.
In a few days I will start bulding my house with earthbags, but I don’t decide yet with what I should fill my bags. In the winter it’s maximum – 20 degrees and not for many days. So I should fill them with clay(yellow) or with slag, perlite? The slag or perlite I have to buy, with about 40$ per ton, it is not more expensive like this? My house have 140 square meters. And the slag or perlite how fix together, inside the bag?
And, I have some autoclaved aerated concrete. Can I use them for the inside walls? They can be plastured with earth?
Please help me, I am a little bit confused.
Thank you!
There are numerous ways to build insulated earthbag houses. You’ll want a highly insulating wall. Here’s the best article: http://www.instructables.com/id/How-to-Build-an-Insulated-Earthbag-House/
I did a quick conversion and see you’re planning a 1,507 sq. ft. house. That’s getting fairly large. We always suggest starting small to learn the basics and refine your technique. Build a tool shed or something similar to get started.
Search our site for confined earthbag. This would work good for your project. The columns will stabilize loose bags of fill.
I’m curious to see if rice hulls would work with this material, never having worked with either but interested in doing so.
Rice hulls will fall through. Try mixing rice hulls with clay. You’ll lose some R-value, but it won’t fall through. For maximum R-value (very cold climates) use poly bags or tubes.
I agree with everything said about the use of the mesh bags with the exception of a lack of need for barbed wire. I would have to see the results of shake tests before I would forego the use of the wire. Has any such tests been conducted, and what was the highest level of shaking on the richter scale did they pass before failure? Superadobe has been found to pass up to a 10.0 earthquake, primarily due to the use of the barbed wire.
Barbed wire and possibly other types of reinforcement are needed in seismic areas. I think they’re talking about non-seismic areas.
Fascinating! I wonder, what makes them worry about building a dome with these bags? In what ways would it be less stable? Even if you did use barbed wire?
Would the advantages and disadvantages of bags vs. tubes be the same as with polypropylene?
They don’t seemed worried, but I am concerned if there’s lack of tensile reinforcement. ‘Volcano’ domes are fine. Rounded domes definitely need barbed wire, but at what point? Very few engineers with the technical know how are stepping forward to help. That and more testing are needed to know how far you can go for sure. So there’s a risk some people will round their dome too much and collapse.
Andre and Fernando have agreed to do an interview. If you have questions about Hyperadobe, please post them here.