Stabilized Earth Bricks

[Aaron Murakami]

Stabilized Earth Bricks are the advanced version of the old compressed earth bricks that just used some cement mixed with the sifted clay dirt.

Stabilized Earth Bricks or SEB's are made from sifted dirt that has at least 15% clay. Normally, clay is hydrophobic so sucks up water.

There have been different mixtures made by possibly either DuPont or Dow for the purpose of making roads for oil companies hundreds of miles out in the boonies. It would cost too much to lay a cement or asphalt road. So instead, just scrape up the ground to expose the ground with the clay and then drive over it with a sprayer to spray an organic chemical on it. Then go over it with a roller to compress it. 24-48 hours later you can drive big rigs on it. It is waterproof and stronger than asphalt or cement. This has been done by the Road Packers Group for a long time. Soil Stabilisation | Ground Stabilisation | Soil Stabilisation Specialists

Then they kept advancing the mixture and applications and used the organic chemical to make bricks for building low cost homes: Low Cost Housing - Clay Brick - Earth Construction - Home

The chemical is so effective it only takes about 1 cup to treat 1 cubic meter of dirt! That is a LOT of bricks. And a 55 gallon barrel is in the $5k USD price range so your bricks are literally dirt cheap.

The chemical switches the covalent bond in the aluminum silicate to ionic and makes it hydrophobic (repel water) so you just made a water proof brick from clay.

When it is compressed and dries, the bricks can be used to build a home in 24-48 hours. So you could dig your basement and that is all the material you need to build the support walls, etc...

Adobe Machines makes some of the best equipment for the best price: Creating Business, Creating Jobs, Creating Hope!

They can kick out hundreds of bricks per day.

I would buy the chemical from the Road Packers Group and use the machines from Adobe Machine.

These bricks are also fireproof and very soundproof. The strength is incredible. You can get dies and create patio bricks, classic red brick size dies, etc... there are even irrigation ditches made from this and parking lots.

The bricks are breathable so stay cooler in the south than homes with a higher R value insulation package.

But up north where it is colder, I don't see this as much of a benefit so I'd coat the inside and outside with Nansulate Home and Industrial Thermal Insulation and Asset Protection Coatings and wind up with a home that is probably close to R100 insulation. Super strength, etc... and dirt cheap - and they look nice (just depends on the design). You can see on the locosthousing.com site that there are many ways to design the look of the houses of course.

[Mark Dorsten]

Aaron,
I did some research into this topic. My son owns a pig farm in Panama and wants to build a couple buildings, including a house. Since adobe is popular and the clay level is good on his farm, we are considering Compressed Earth Blocks (or Stabilized Earth Blocks).

Compressed Earth Construction or Adobe works best in hot climates where it cools off at night. This is because of the U-factor. We are all familiar with the R-factor of insulation. That is resistance. The U-factor relates more to mass and speed of transfer. For a given locale there is an optimal thickness of thermal mass wall. Your goal is to never allow it to complete heat cycle. In other words, you want the sun to set and temperatures to drop before the heat of the day makes it all the way through the wall.

If you cut the wall into thin vertical sheets, the outermost sheet would experience the greatest temperature cycle from midday to midnight. Hopefully the innermost sheet, facing the living area, will remain at the mean temperature for that local. You can cheat the temperature down with roof overhangs that keep direct sunlight off the exterior surface of the walls. You can also circulate the cool night air through the house.

I created a rather basic Excel spreadsheet for the project. I tried to attach it but failed. If I don't figure it out soon, I will just include a hyperlink.

[Aaron Murakami]

Hi Mark,

I hope your son has great success with the project in Panama.

These bricks breath and that aids the cooling, but I'm not so sure we want that up North.

I'm interested in applying multiple coatings of Nansulate on the outside and inside of the bricks to acts as a radiant barrier and it also adds a significant R value. Nansulate is supposed to be breathable. I'm interested in locking in the heat that I make in the winter. Not too concerned with keeping heat out in the summer.

Do you know of anyone using these bricks successfully in cold climates?

[Mark Dorsten]

I talked to a gentleman in Alabama who had a used machine for sale. He built a house in Missouri which gets quite cold.

Because mass stabilizes temperature to the mean they will work in a colder climate but you will need to add "regular" R-value insulation. But realize it will be more effective because you are not insulating to a variable temperature but instead to the mean. I will use St Louis, MO as an example; NOAA Climatology and Weather Records show an annual average temperature of 56 to 58 degrees for the last 20-years. The summer mean is 76 to 79 and the winter mean is 30 to 38. If you used fans at night, you probably would not need A/C in the summer. In the winter you would be insulating against a 35-degree temperature differential.

I looked at Nansulate and liked it. Perhaps you could build a storage building first and look at the temperatures. Also remember these are NOAA numbers and I didn't check all the details on their definition of "averages". The point I was trying to make regarded temperature swings being eliminated with a high U-factor wall.

Mark

[Jeff Pearson]

Here in Taos it can get down to -20 in the winter. Adobe bricks is the traditional building material here. They dont have much R-value. They do have good thermal mass (temperature storage). Apply insulation to the outside to keep heat in. as long as the inside can breathe its OK if the outside is sealed. So yeah, adobe bricks work great in cold climates

[Jeff Pearson]

oh yeah, Aarron, you DO NOT want to insulate the inside of the adobe, just the outside. If you insulate the inside, you no longer have a thermal mass temperature 'storage battery' cause you just insulated it away. The more thermal mass you have, the harder it is to change the temperature of it, the more stable your temperature is. So dont insulate your U-value out of your house. Also, stabilized bricks are normally just used on the first couple courses, after that just plain adobe; and asphalt emulsion is a cheap stabilizer. Of course, I wouldn't make bricks except for maybe the first two courses, I would do bottle cob
https://www.facebook.com/photo.php?f...type=3&theater
https://www.facebook.com/photo.php?f...type=3&theater
https://www.facebook.com/photo.php?f...type=3&theater
These pics are of an 18" thick mud cob bottle wall. It has since been through 2 winters (no one else has worked on it since I left ) and the only deterioration that has happened is the top layer of bottles fell off.
The bottles save on cob, are an alternative to a form, and you dont have to move the dirt twice; once to make a brick, once again to put it on the wall. Just make the mud and put it into place. By the bottles being a kinda form, once the mud sets up a little bit, You use a level to plumb the bottles. The temporary greenhouse attached to the bus is made the same way except I used cans on a lot of it so it is only a 5-6" thick mud wall. I was impressed with how strong a that thin of a mud wall is.
It dont have to be 18" thick. It is more standard to make a 12" thick mud bottle wall
This isn't research, it is what I did for a living.

[Aaron Murakami]

Jeff, insulating only the outside makes sense if we do want to cover the outside. Going with that theme, perhaps for the northern climate, simply add about 10 layers of nansulate on the outside and that's it. That would accomplish the same and would allow the natural look of the bricks to shine through. I guess if we really wanted to get gung ho, we could always have the outer walls as 2 layers of bricks with some air space between them.

All the stabilized earth brick homes I've seen (in pictures) are 100% earth bricks up to 3 stories high.

Below is one home example and I think it looks pretty good.

Also, you mention asphalt emulsion - the chemical stabilizer I'm talking about actually changes the covalent bonds in the aluminum silicate to ionic and makes the clay hydrophobic - a true water repelling brick. Does the asphalt have that benefit?

Below is from Low Cost Housing - Clay Brick - Earth Construction - Home

Welcome to Low Cost Housing International (LCH)

Stabilized Earth Brick (SEB) Technology

Why choose LCH?

As a successful part of The RoadPacker Group of companies we benefit hugely from the soil stabilization research and development undertaken by RoadPacker International Ltd. LCH offers a complete package for the provision of low/medium cost housing. Our housing technology is very simple – an interlocking clay brick system, treated with our ionic clay stabilizer formula. This alters the clay and improves its engineering properties - including compaction, density, bearing strength and safety (i.e. – fire). This provides a low cost, durable product that can meet the needs of the millions of low cost housing units required annually around the world.
LCH has provided products and services to the housing industry since 1998. We have expanded products and services to include special community re-development projects, incorporating environmental management with effective social and community sustainable modelling.
What's it all about?



The primary purpose of LCH/RoadPacker, SEB technology is to support and encourage low cost housing in any country where there is a distinct lack of conventional housing. Our biggest advantage - is that our response is immediate. Not only can our product be used in the planned creation of new permanent communities - but more dynamically in the unplanned event of natural disasters. When typhoons, flooding, and earthquakes render thousands of people homeless - the immeasurable benefits of this system of home building really kick in. The ability of disaster rescue units to offer immediate effective assistance is dramatically enhanced because they need very few raw materials. They can move into a declared disaster area and begin to provide the rudimentary requirements for that community to return to a position of normalcy.
Benefits of the SEB building system

• it is truly low cost
• it is the most energy efficient building system
• it produces attractive buildings of high strength
• it has a host of environmental advantages over other building systems
• it uses the most widely available and least expensive building material in the world - earth
• it involves unskilled local people in erection of the buildings - thereby encouraging 'ownership'.

[Jeff Pearson]

You still only insulate the outside because the thermal mass of the bricks works for you both in the winter and summer in stabilizing temperature. The thermal mass 'battery' works both ways. It helps heat in the winter (store heat) and stores cool in the summer (cool storage) relative to outside temperature. You want that mass to be part of the inside of your house to get those advantages from it. The insulation is to prevent your stored heat or cool in the mass from going away outside. Mass is very effective at stabilizing temperature. Its not just about insulation.

[PaBloM]

Well there are many factor in a house to keep with the proper temperature....the most efficient i know is wider walls and and roof.