The California Institute of Earth Art and Architecture is a charitable non-profit organization that was founded in 1986 by Nader Khalili (1936-2008). They focus on developing truly sustainable earthen architecture. Their primary building method, nicknamed superadobes, uses long sandbag tubes filled with a semi-moist mixture of earth, cement, and water. The rows are laid with barbed wire between the sandbags in a similar fashion to other methods of earthbag construction.
I’m not sure how this method compares with building with sack-size earthbags. The inclusion of cement in the earthen mix must give the walls some added water resistance, but even unstabilized adobe bricks can hold up to years of weathering, and centuries if protected from direct rain. In any event, if you’re considering building an earthen building, here is yet another way to build with the stuff under our feet. Learn more on the Cal-Earth website.
This post was sparked by a comment from Steve, one of my long-time readers. In a nutshell, he suggested that people would be much better off living in handmade homes than living in machine-made prefabs.
Like most people, modern prefab designs grab my attention. I suspect that it’s their product-like polish and our learned weakness for nifty consumer gadgets that incites us to be drawn to shiny prefab designs. So naturally when I see a shiny design concept that looks like it has potential my initial reaction is to share with my readers.
But I must completely agree with Steve on the issue of metal boxes, we deserve better. Prefab homes aren’t really all that sustainable considering that they are made from a bunch of factory-made components. I actually chortle to myself every time I run across a luxurious modern LEED-certified home on display over at Dwell and Inhabitat. I just can’t see how tons of glass, steel, and engineered lumber could possibly add up to an environmentally friendly housing solution.
To be quite honest, I think the whole LEED-certification thing is a joke. I just don’t see how these hermitically sealed high-tech boxes can be considered sustainable architecture after adding-up the impacts created by all the factories and mining operations necessary for producing the prefab parts.
Which leads me to a construction method that, in my humble opinion, blows away any new-fangled LEED-certified concoction… earthen homes.
When I first read about Ryo Chijiiwa’s tiny cabin on Tiny House Blog I was fascinated by the adventure this fellow was on. He quit his job at Google, traveled America, and is now working to setup a more comfortable place to live on the remote property that he recently purchased in northern California. You can read about it on his blog, Laptop and a Rifle.
But what I’ve been obsessing over for days is a simple solution that someone like Ryo could theoretically implement for a little money and a lot of sweat equity, an earthbag tiny house. Below is my earthbag daydream for simple sustainable living. The main room of the house is 12′ by 16′ and the bathroom is just 6′ by 6′.
Three months out of the year this is the home of Samuel Gray. This adobe casita located near Abiquiu, NM and in just a few years will be Sam’s full-time residence. It measures 12′ by 10′ on the exterior but due to the thick adobe walls has only about 86 interior square feet. He built it for less than $3000 and it’s powered by a simple low cost photovoltaic solar system. Continue and read about this Adobe Casita in Sam’s own words. There are more photos too.
Here’s Sam’s description of his tiny home:
The footprint is 120 sq ft (12′ X 10′) but the thick walls reduce the interior living space to 86 sq. ft. That’s just enough for a small bed, a fold-down desk, a small kitchen counter and some shelves. The only wood in the structure is in the roof. The inside wall treatment is mud plaster made from white clay which is abundant in the area. The outside is stucco over 2 inches of rigid insulation.
I built it from adobe which was mortared with mud from the building site. The foundation is a 10″ X 10″ collar beam on top of a 20″ X 20″ rubble filled trench. This foundation system provides adequate support for the heavy walls and took only 1 square yard of concrete to make.
The total cost for the casita was a little less than $3,000. I could have saved 1/4 of that by making my own adobes. Soil from the site is ideal for adobe but I had time constraints at the time so I bought them from a nearby adobe yard.
The local power company wanted $12,000 to run a line to me so I built my own electrical plant for $1,902. My homemade system consists of 2 PV panels, 4 golf cart batteries, a charge controller and a small inverter. That provides enough electricity for the casita and the water well. The best part is there’s no electric bill to pay.
Thanks for sharing this great little house with us Sam. It’s great to come across people making their dreams come true in tiny low cost small homes. Your home is especially well done and an excellent example of how a small space can be comfortable, affordable, and attainable.
Ziggy’s cob house at the Dancing Rabbit Ecovillage is complete. He’s also posted a lot of detailed information about the construction process, cost, and sweat-equity required to build such a house on his Building a cob house blog. The house is about 200 square feet and includes a reciprocal roof and rocket stove. Ziggy estimates that it took about nine months of full-time work to build the house. His total cost was about $4000 but $1000 of that was labor so you could actually build this house for $3000 if you did all the work yourself. Take a look at Ziggy’s cob house, aka GOBCOBATRON.
I was contacted recently by Michael Thompson a fellow I follow on Twitter, and a self-taught rammed earth expert. He and I share a passion for low-cost building techniques. He asked me to do him a favor and whip up a 3D drawing of his rammed earth wall former hat will serve as course material for his rammed earth workshops. It only took about an hour to draw it up. It’s amazing how simple the former is and how with some sweat equity dirt from a building site can be transformed into walls.
For £99 you can attend one of his 2-day rammed earth building workshops in Norfolk. You’ll learn about soil suitability, footings, design, ramming techniques, bond beams, window openings, and more. By the end of the class you’ll know what you need to get started on your own rammed earth shed or tiny house. Continue reading to see more views of my drawing, the SketchUp file itself, and a video that shows how it’s used.
I really like the ingenuity of the fellow behind the website naturalhomes.org. This is the website dedicated to houses built from natural materials like cob, adobe, straw bale, stone, dirt, and so on. You’ll find examples of natural homes from all over the world. Some are big but many are tiny houses. Oliver Swann, the fellow behind the website, has been busy putting together all sorts of cool ways of exploring the world of natural and tiny homes. Here are a couple of good examples of what I mean.
Owen Geiger over at Earthbag House Plans has been busy. He has posted the preliminary designs for about 77 plans for earthbag homes available on his newest website.
An earthbag home is essentially a home made from the dirt under your feet. It’s scooped up and placed in bags like old grain bags or sandbags. They are then laid up like bricks and you can build strait walls, curved walls, and domes.
It’s probably the fastest and easiest way to build walls and the best part is that it’s as cheap as dirt. To learn more about building with earthbags visit Earth Bag Building. Here is a sample of what you’ll find:
Cob is earth, sand, and straw. It’s similar to building with adobe but instead of making blocks to stack-up like with an adobe house, cob houses are built-up while the mud is wet. The material is essentially the same, the construction process is what differentiates cob from adobe.
The most obvious design difference is that adobe homes look more square and cob homes look more organic and sculptural. This is due directly from building with mud when it’s dry (adobe) versus wet (cob). Theoretically you can achieve a similar aesthetic with both methods but cob’s natural tendency is to look much more organic and free.
Brian Liloia is building a tiny cob house at the Dancing Rabbit Ecovillage in Missouri. Last summer he finished the walls and roof. His house has several very interesting design features like a reciprocal roof, a rocket stove, and earthen floor.
The reciprocal roof is a self supporting round roof that’s often made from thin logs that are then fastened together and covered with a more weather proof roofing material. Cob and adobe homes need a good roof to keep the water off their earthen walls.
The rocket stove is a built-in earthen stove with a long flu that snakes through the cob walls and built-in benches. Adobe and cob provide a great deal of thermal mass so that once you heat it up, or cool it down, the temperature of the room is maintained by the mass of the building. The rocket stove in Brian’s home should keep it very warm through the cold Missouri winters and cool in summer so long as he doesn’t light too many fires.
Sealed earthen floors can be very comfortable to walk on and surprisingly clean. They require careful cleaning and will eventually need resealing but they are a far cry from what you might imagine a dirt floor to be like to live with. Linseed oil is often used as a sealer.
Below are some photos from Brian’s blog. He’s documented his design choices and progress in great detail with photos. Visit Brian’s blog to learn how to build a cob house. For more about building with cob visit I Love Cob. There are also many good books on building with cob if you’re serious about building a cob house in the future. One good book on the topic is Building With Cob: A Step-by-step Guide. Photo credit Brian Liloia and friends.
Julia (my wife) ran across this papercrete house website recently. Papercrete is a simple and inexpensive way of building walls from paper pulp and cement. Normally concrete blocks are a mix of sand, gravel, and quite a bit of cement to hold the block together because the sand and gravel offer no added binding ability. Paper on the other hand is fibrous so less cement is needed. The end result is a inexpensive lightweight insulating construction material made from 95% recycled material.
You make papercrete by taking old newspaper, phone books, and/or cardboard, and mixing it up with a lot of water until the paper is pulped. Then you add the cement and voila… yuckie sticky globs of goo that make perfect block walls or sculpted structures. It sounded a lot like working with adobe or cob to me except of course papercrete would be much lighter when dry and have more of an insulting factor.
Adobe, cobb, and concrete are great for thermal mass but they don’t really insulate the way that straw bales, insulated panels, or even insulated framed walls do. Masonry walls simply regulate the interior temperature by slowly heating and cooling. For example on a hot day an adobe wall heats up slowly and the heat travels through the wall at about 1 inch per hour. By the time the evening comes around the heat of the day finally makes it way through the thick wall and is released to warm the interior at night. The wall then cools at night and stays cool all the next day. This simple cycle makes adobe and other masonry materials attractive in hot climates.
But in most climates insulating walls tend to be more usable because they regulate the interior temperature by creating a barrier between the inside and outside. I suspect papercrete provides a mix of both, depending on what you choose to put into the mix. In fact I bet if you mixed your sun facing wall with a bit of gravel, sand or adobe you’d be able to take advantage of the thermal mass qualities of a real masonry wall. Then mix your insulating walls with just paper and cement to hold in all that regulated temperature. Doing it this way would give you a nice blend of the two properties and result in a nice passive solar house.
I was especially excited to see this inexpensive approach. Papercrete definitely deserves some exploration. Here are some other papercrete websites. Enjoy!