United Earth Builders, the Earth Home Builder and our other various projects

Hey All! I just wanted to share some of the projects I have participated and led with my partner Fox at United Earth Builders! We have been building, near non-stop, for 6 years and are hoping that earthbag/superadobe/whatever you want to call it, spreads across the globe. We love it to no end!

We have re-purposed a levee builder in order to build earthbag homes and just wanted to share it with the Permie forum!

EHB

We also have hand built a natural dome/vault structure with 90% reclaimed materials from the Mojave! Here is a video of our insulation technique that we researched and used from Patti Stouter at buildsimple.org.

Hyper-Wattle:

Here is a video of a project we supervised in LA County:

One other project from last year in Niger Africa teaching Tuareg Nomads

Nomads: http://nomadfoundation.org/best-mission-ever
http://nomadfoundation.org/earthbag-building-finally
http://nomadfoundation.org/earthbag-decorations-the-art-program

Write up in ARCHITECT Magazine:

http://www.architectmagazine.com/technology/using-additive-manufacturing-to-build-with-materials-sourced-from-the-jobsite_o

I hope you all enjoy! Check us out at www.unitedearthbuilders.com

Hi James, thanks for the report on these very interesting innovations.

I myself had been interested in hyperwattle walls but couldn't find much info or reports of practical experience.
Sure it is a simple technique, but even simple techniques have "gotchas" that I'd rather read about than experience myself, lol.

I have a question about your hyperwattle insulation.

Everything I've read so far says that a clay-straw wall should dry for several months during which time it needs to be open to the air on both sides.
In the video it looks like you applied fresh wet wattles directly against the earthmass walls.
Of course the drying guidelines were developed by tradition in germany where the strawclay technique originated; maybe in the hot dry climate in which you were building drying happens much faster?
Maybe there are drying guidelines specific to desert conditions that I haven't noticed, since I'll be building in cold damp New England.

Another question, had you also mechanized the filling of the wattle bags?

My pleasure

We did apply the wet hyper-wattle to the structure and to us, it looked breathable enough to do so since we do have a naturally dry climate with high winds that make the clay dry incredibly fast. Now we were afforded the benefit of being out of country while it dried so we did allow the structure to dry for a couple of months before we applied the earth, clay and straw plaster bond coat before the NHL 3.5 lime plaster. We did still have a moldy smell in the beginning of the drying phase but dissipated after about a week. We allowed the structure to be fully exposed to the SoCal sun and covered if rain came in (rare).

One beautiful thing about hyper-wattle insulation is that they can be pre-made and placed after drying. So for example, they are light enough (especially after they are dry) that one person of reasonable strength can lift and place a 10' length. So if you are able to produce all of the insulation, allow to dry for X amount of time, then place afterward, that would work well and ensure your wattle is completely dry. Granted they will be a bit stiff but that, in my view, is not an issue because they are still malleable for dome applications. Vertical, straight walls are easy )

We haven't yet, but are looking to use the EHB, or an alternative to make the hyper-wattle as well.

James thanks for sharing all that. Did you say Mohave, CA. I was there working on the Stratolaucher last year. Where are you getting the NHL? Did you say you brown coat on top of earth plaster with 3.5 then 2.5? I don't have access to the NHLs here. I would have thought finish with 5 since it has more cement or are you sealing the final coats with some sealer? Does CA code allow for this time of construction or are you not being code enforced? And what are the bags made of and where did you get that blue skid loader attachment?

Thanks James! That rules out wet wattles against cob in a wetter, cooler, less windy climate, as I suspected.

I have considered drying some claystraw in advance. I was thinking of blocks, but maybe wattles could work.
Have you ever done this?

Can you give an estimated weight for a dry 10' wattle? And would that be 12" diameter round?
Would a 10' length actually hold together for carrying and placement?

I may be able make some in advance in a nearby location, before my foundation and frame are done,
and given the long drying time necessary and the short building season, it seems worth considering.
Every week counts.

I am planning straight walls.
If some wattles were made and dried in advance, what would be the best way for me to combine them with others made and dried in-place,
given that I won't have desert sun and wind to dry the ones made in place? IE, they'd need to be open to the air on both sides.
Maybe layer it vertically?, some dry then some fresh etc.

Hmmm, maybe a core of pre-dried, with 2-3" of fresh wet claystraw on either side?
That thin it would dry okay if only open to air on one side? What do you think?
Have you got any idea what would be the optimum thickness of an outer crust sandwiching pre-dried wattles?
Thin enough to dry well but thick enough to glue the wall into a single unit.
Oooh, then the wall could exceed the traditional 12" limit, even up to the width of strawbales.
Wow, this might be a way to approach the insulative value of strawbale walls without risking mold.

Also, can you suggest sources for the bags?

James,
Awesome projects! Few questions:
1) What's the daily square foot of tamped wall built when mechanized with EHB (# of hours and laborers)
2) for the Mojave dome, what's the ratio of hours between the EB and Hyperwattle? What's the dome interior diameter?
3) what's the Mojave vault formwork--is that precast or plastered EB? What's that interior diameter?
4) what was the formwork/armature used on the LA county barrel vaults? Their internal diameters?
5) I'm sure people would like to know, where are y'all and your machine located?
6) would you use the smurf ent again or switch to uf/mc/metal flex?
7) would you feel comfortable doing round vertical walls mechanized with EHB?
8.) when are you gonna get yourself a cheap pneumatic tamper there is no turning back when you do. I use mine, a small front end loader and scrap 2x-ply slip formwork. But your setup is more versatile. I bet you could rock a Pico Jack with a small plate as well, and then just share the diesel if you aren't using a monster compressor when spraying
9) you seen the front end loader and the pto 3 point huge barrel mixers? Does your EHB have a mortar mixer style auger inside the bucket to mix plaster and drive over to the wall?
Chris

Terry Ruth wrote:James thanks for sharing all that. Did you say Mohave, CA. I was there working on the Stratolaucher last year. Where are you getting the NHL? Did you say you brown coat on top of earth plaster with 3.5 then 2.5? I don't have access to the NHLs here. I would have thought finish with 5 since it has more cement or are you sealing the final coats with some sealer? Does CA code allow for this time of construction or are you not being code enforced? And what are the bags made of and where did you get that blue skid loader attachment?

Joshua Tree actually ) We bought the NHL from a local company, Solstice Eco Building Supply who is a dealer for Transmineral. What we did after the hyper wattle layer was apply a earthen straw plaster to shape the dome and vault which acts as a bond coat. Next we did a 'crack coat' which is intended to crack due to the difference of material. The clay and the lime. We used a sprayer so there was little cracking because the sprayer bonds the plaster so well. We then applied 2 more coats, brown and scratch and are now waiting for winds to calm in order to apply the final color coat.

NHL 3.5 and then 2, this was recommended by Transmineral due to the dome shape we are applying to. 5 makes sense for durability, I agree.

We haven't decided to use a sealer but are looking into paints and sealers, but overall the rain isn't too bad here, driving yes, a lot in a small period of time yes, but not sustained. And overall the lime looks amazing.

We are building this as an R&D project under the 120sf guideline, so no code enforcement. It's going to outlast a few generations probably anyway so safety isn't really an issue that I personally foresee.

The wattle bags are polyethylene and we sell them ) http://www.unitedearthbuilders.com/#!bag-supplies/c1o1j

Our store is going through renovations but if you would like to order simply email us.

We also sell the EHB and have a deal with a mid-west company called Progressive Innovations who we collaborated with in order to make the dream happen. They provided the machine and I was able to show them how to use it

[quote=Susana Smith]Thanks James! That rules out wet wattles against cob in a wetter, cooler, less windy climate, as I suspected.

I have considered drying some claystraw in advance. I was thinking of blocks, but maybe wattles could work.
Have you ever done this?

Can you give an estimated weight for a dry 10' wattle? And would that be 12" diameter round?
Would a 10' length actually hold together for carrying and placement?

I may be able make some in advance in a nearby location, before my foundation and frame are done,
and given the long drying time necessary and the short building season, it seems worth considering.
Every week counts.

I am planning straight walls.
If some wattles were made and dried in advance, what would be the best way for me to combine them with others made and dried in-place,
given that I won't have desert sun and wind to dry the ones made in place? IE, they'd need to be open to the air on both sides.
Maybe layer it vertically?, some dry then some fresh etc.

Hmmm, maybe a core of pre-dried, with 2-3" of fresh wet claystraw on either side?
That thin it would dry okay if only open to air on one side? What do you think?
Have you got any idea what would be the optimum thickness of an outer crust sandwiching pre-dried wattles?
Thin enough to dry well but thick enough to glue the wall into a single unit.
Oooh, then the wall could exceed the traditional 12" limit, even up to the width of strawbales.
Wow, this might be a way to approach the insulative value of strawbale walls without risking mold.

Also, can you suggest sources for the bags?[/quote]


We have done some blocks recently and they're great, but haven't found an application yet. I surmise that it would be cheaper than framing up for a light straw clay application but I would do some tests first. For domes, it isn't as efficient I think. The containment of the bag is simply divine. It really allows for fluid application and creative curves and designs.

Estimated weight? Good question. I am reasonably strong and can lift a 14' wet length with no problem but I would estimate no heavier than 50lbs. It's awkward but contained in a bag but I would say it's like lifting a large worm. Ours was 8" around when stuffed but the bags stretch to varying sizes and the diamonds vary as well. 3/8" and 5/8" diamonds if I recall and the 9" wattles stretch to 17" so it really requires some awareness of how much you are filling the bag. The 10' lengths will hold, the bag is strong, but care is always a good rule of thumb. Try not to get the bag caught which may cause it to stretch. When dry simply be much more careful. Compacting the bag is necessary but not to the point where it's losing the R-value. What I mean by that is the air pockets created by the straw should not be compacted like tight bricks.

My suggestion would be to place some vertical 2x2's or even #4 rebar at 5' intervals and stack the wattles on top of each other like you are suggesting. Let's say 6 pieces of lumber or rebar vertically at apx 5' internals and spread about 9" apart. Like a vertical drying rack. That could work well. Given enough time they should dry according to the humidity in the air, sun exposure, etc.

Attaching them to verical walls will require anchor points in your wall, which we did with wooden dowels and zip ties. They aren't so heavy so it doesn't take much to attach them and plaster strengthens it all.

Overall I would allow the wattles to dry out first and then apply clay plaster just to be sure there is not mold. Spraying it all with a lime wash is a good way to abate mold ass well. Once you crust the wattle, it is tough to move too.

We sell the bags online, here is a link and if you would like to order some, email us :)

http://www.unitedearthbuilders.com/#!bag-supplies/c1o1j

Christopher Steen wrote:James,
Awesome projects! Few questions:
1) What's the daily square foot of tamped wall built when mechanized with EHB (# of hours and laborers)
2) for the Mojave dome, what's the ratio of hours between the EB and Hyperwattle? What's the dome interior diameter?
3) what's the Mojave vault formwork--is that precast or plastered EB? What's that interior diameter?
4) what was the formwork/armature used on the LA county barrel vaults? Their internal diameters?
5) I'm sure people would like to know, where are y'all and your machine located?
6) would you use the smurf ent again or switch to uf/mc/metal flex?
7) would you feel comfortable doing round vertical walls mechanized with EHB?
8.) when are you gonna get yourself a cheap pneumatic tamper there is no turning back when you do. I use mine, a small front end loader and scrap 2x-ply slip formwork. But your setup is more versatile. I bet you could rock a Pico Jack with a small plate as well, and then just share the diesel if you aren't using a monster compressor when spraying
9) you seen the front end loader and the pto 3 point huge barrel mixers? Does your EHB have a mortar mixer style auger inside the bucket to mix plaster and drive over to the wall?
Chris

Great Questions!

1) At max with an optimal crew of 8 we can lay about 640 feet per day with one EHB. 8 hour day. We do compact with a vibratory plate compactor 21". The compacting is the slowest part at this point.
2) At this time we cannot build domes with the EHB. We are looking into experimentation, but with little demand for the domes (although people love to romanticize about them) it's not financially viable at this time. The Mojave/JT dome was all built by hand, but if it was built by a machine it would take a day or two. It's not that much bag. The interior diameter is 8'6".
3) Here's links for the dome bag work/wattle/plaster:

http://imgur.com/a/ODhPm
http://imgur.com/a/qzBmF
http://imgur.com/a/nydtH

4) Prefab angle iron forms bent and bolted together. We skinned them with sheet steel, perlings and it was a big deal. We tried box steel and rolled steel as well but I think the right angle iron worked the best as it maintained the best shape and strength. The diameters were 8',12',14' & 16'. They were massive and all built by hand. The total cost was over $1,000,000 USD.
5) We are located in Joshua Tree, CA. Beautiful place, I recommend visiting as we have several earthbag structures built here including (http://www.bonitadomes.com/)
6) I would use it again, I like it. The others are great too and I hope to test out a variety of ideas I have in regard to installing electric because it's not incredibly smooth installing any of those products. The bag walls may vary, bumps are here and there, uneven, etc.
7) I would absolutely be interested in that. Roundhouses are so practical and feel nice on the inside. At this time our max height is 7' safely with a 12" bond beam to secure the roofing. We haven't gone 2 story yet due to the limitations of the skid.
We usually rent them because of cost, but I would like to get a mini. So easy to carry and as of now we use the loader skid to move them around once the wall gains height.
9) I have and I would love to get my hands on one! They would make life easier in some ways especially when code calls for concrete in the bags. Elephant trunks and barrel mixing wont cut it when it comes to affordability and expediency. We have a 12" auger in the hopper. It's incredibly powerful and can mix concrete but not over the long term. Breaks chains. Direct drive would be better but that's future

Thanks!

Yeah Yahmes!

Just want to make some clarifications about the NHL plaster layers over the earthen base coat in case others are using this as a guide. First step is to spray the pre-moistened earthen base coat plaster (or cob, adobe or similar) with lime water (1 part NHL 2 or 3.5 to 10 parts water) the day before plastering (or multiple days in a row before plastering) and again the day of plastering. This helps stabilize friable earthen materials and begin the bonding of the 2 different materials. The first coat they put on is called the "bond coat", to aid as a bonding layer between the earth and NHL plaster. In their case NHL 3.5 was adequate. In climates with more extreme freeze-thaw action happening NHL 5 is recommended. It's expected the bond coat will crack which I'm guessing is why James called it a "crack coat", but that's not the name we're promoting for obvious reasons. Then over the bond coat the scratch and brown coats are applied. That was with NHL 3.5 on this project, and in more extreme climates' NHL 5 is often used for the scratch coat and NHL 3.5 for the brown coat.

The finish coat will be NHL 2 which is the softest, most flexible, and most breathable of the three NHL types. It might seem counter intuitive but the time tested approach for durability is to have the plaster layers go from hardest underneath to softest and most breathable on the surface. That allows for the most flexibility and highest crack-prevetion qualities. And it feels softest to the touch, which is nice. You wouldn't want to do an NHL 5 finish coat. Of the three different types. NHL 5 is the hardest, most brittle, and least breathable. NHL 5 is also the most hydraulic so it sets up the fastest. Not what you'd want for a finish plaster. NHL 2 is great on its own as the final coat. No sealer is needed. All limes are sacrificial materials that slowly wash away over time and can be maintained simply and easily with a basic NHL 2 lime wash, which can be tinted to match the existing colored finish plaster coat, or another color if you want to change it up. I'm guessing it will be many years in our arid Mojave desert climate in Joshua Tree beforee any lime washes would be needed though.

Please note that different climate conditions, building designs & substrates will call for different approaches so it's best to seek guidance on the plastering approach from someone who understands NHL plasters before purchasing the materials. If in doubt, check in with Michel at TransMineral, the west coast importer-main distributor for St. Astier NHL. He's a great resource.

Cheers!

Nicholas Holmes
Solstice Eco Building Supply
Holmes Ecological Design & Construction
(800) 542-0728

When I worked in Mohave last summer we could not be outside more than 10 mins before we began to dehydrate, 110 F but the high winds keep it cooler. Solar and wind turbines everywhere. I also have a home in So CA and grew up in El-Segundo, CA been all around the US since and I'm here to tell you that climate is like no other. I figured St. Astier NHL they have some interesting claims about their very expensive limes (imported from Europe if I remember right or get their raw materials there. I like the French chemist there interesting fellow) I and the other big lime manufactures don't agree with. I also think some of the building methods with multiple seams especially verticals vs monolithic here would struggle in heavy snow and wind driven rain or building climate zones 5-7. Crack coats would not be a good idea there, or marine type climates with alot of vapor from high humidity and/or hot/cold cycles or large daily swings unlike CA. There we want a more cement like outer layer water and ice barriers for erosion and abrasions, as a matter of fact in much of code it is required structurally for braced wall methods. Dome roofs would be a challenge. I've seen alot of high portland cement stuccos and building materials down by the oceans be eaten away from salty and corrosive moist acidic air. I'd like to see how a NHL 2.5 does over decades. Deadman thermal bridges or corrosive steel rebar/metals in moist clay or lime in these cold/wet climates would not be a good practice.

I think Premier mines in Nevada, IIRC you might look at Magnesium Chloride and a reactor in a mag plaster since your in a R&D phase. The salt content will be the trick but once you get it it will out perfom the limes in a lot of different ways. Companies like Durisol and Faswall already have some proof. Im about ready to pay them a visit myself. They also make a shrinkage reducer admix that may help stabilize high plastic clays as a bond coat: http://www.premiermagnesia.com/concrete_shrinkage_reduction that would help with acid, salt, intakes and efflorescent. I do believe IIRC the NHLs will have a harder time bonding to clay since they have little to none....adding some might help.

Anything that kept the Mohave green snake or desert varmints out of my home work for me

I'd be interested on how these building's hold up to CA seismic events and things like how far the dome roof can clear span. Going to be hard to beat reinforced strawbale:


Good thing there is we have new 2015 international saftey code to follow. If you look at that code the cement skins and mesh take the seismic loads at the foundation and roof joints. When I say cement I am referring to NHL 5. In your methods the weight at top is going to be the challenge to resist ground accelerations. In that case the NHL 5 or Type S will help react shear wall and fulfill code braced wall requirements.

Sealers: I found siloxance or silane effective on earth/lime, the ones with a natural silicone vs synthetic with at least 40% solids. It takes some adhesion testing. One could probably mix that right into the final mortar sprayer along with iron or earth oxide pigments.

BTW: For those interested. I believe those are accelerometers and stress/strain gauges on the strawbale stuccos/plasters that are used to determine how far the plaster will stretch (or it's plasticity or elasticity) in measured lengths before it cracks, that determines how much structural stress it can take before it cracks/fails in a seismic event. If they did that right or had the $$ there are CO2 pumps to put the temps at freezing and high heat/humidity cycles. That info is used to develop safety code, or mix ratios in the code tables. The ductile core strawbale is shock resistant so alot of load is moved to the stiffer skins(stucco/plasters). Without the ductile core more load will be transferred to the skin ties at the foundation/roof. That's one big A$$ shaker table, the ones I have experience with are much smaller but same concepts.

These methods will probably need to go through a similar process before code is adopted. To gain international code compliance a letter of ICC intent (International Code Council) compliance would need to be submitted with the same type of lab and international field testing. So there is ALOT that goes into international code. After that each jurisdiction has to determine if it fits into their climate zone, soils, etc.....They may adopt in-part, none, or modify it.

The highest skins loads will be at the clay to lime bond scratch coat and outer most finish coats. The brown coat will transfer between the two so it is critical too, along with good density transitions and continuous load paths around the walls, roof, foundation usually through a well bonded wire mesh. This is nothing new (stiff skins and a ductile core(like honeycomb with fiberglass or graphite continuous cloth skins and/or chopped fibers impregnated into the skins) we been doing it in other industries for decades with excellent results.

If I remember correctly (IIRC?) strawbale passed 200% of one of the largest earthquakes in CA. Whole wall r-values ~2-3.0/inch.

Just goes to show some of the best natural building methods are not in IRC (International Code). The 2015 Strawbale adoption was a huge milestone for us. I/we are now able to take it to our jurisdictions for adoptions, no need for expensive structural engineers(PEs). It's a start! Ca, NM, AZ also has some great earth codes for adoption into local codes. These states are making a mark and raising the bar for the rest of the country to follow, to include the companies above, and I think we are beginning to understand how they can be adopted in any climate zone under any structural conditions.

Good job guys I'll be back home soon will look you all up :0)

BTW: I had a good chat with Premier again today and am getting some home grown MGO, let you all know at permies.com the outcome after some testing. They have new better chemist I need to contact tomorrow. It will be the new render of choice in the US of A at reasonable cost, once it is better understood and the bugs are worked out. That and the new hemp growth. A MGO/clay shotcrete or gunite single coat on hemp if you can find a mix that does not dry to fast and clog the gun would be a worth looking at, @ 100% petrified saturated hemp.

These kind of houses were adorable. They just had a perfect out-sitting and actually made many aspects at that period of time. We can see this kind of houses today also, but many of us are having the idea of a safe house. So in todays generation the houses are packed with the impact windows and doors. To establish a new home renovation techniques impact windows coral springs and impact windows Broward also makes the best of securing the home with the absolutely fantastic replacement window items.