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The Boden-Haus Begins



A Baking Studio via Google SketchUp

Sandstone was the closest of the default textures to rammed earth.

Boden \b┼Źden\
1. Soil
2. Earth
3. Base

Haus \'haús\ 
1. House
2. Building
3. Establishment

"Boden-Haus" is German for "Earth House."  Before I can talk more about the Boden-Haus, I must explain rammed earth a bit for those of you who are unfamiliar with this most ancient of construction methods.  

It is with great reluctance and greater difficulty that I attempt to explain rammed earth and my interest in it.  In fact, I am so reluctant, so difficulted, that I just typed "quote reluctance" in Google, and the fruit of my search was this quote from Jean Racine:
There is nothing so easy but that it becomes difficult when you do it with reluctance.

Ah, that explains that.  Let me continue more boldly than before.

Rammed earth construction is a straightforward process with amazing results: one places soil into a formwork and compacts it into layers, making the walls of a house, a house that can last for hundreds of years.  The rammed earth house is warmer in the winter and cooler in the summer than most buildings made of other forms of constructions.  Thick walls of unfired earth dampen noise.  With walls resembling stone, a rammed earth house is virtually fireproof and windproof.  The walls are too dense for vermin to gnaw into, too dense for vegetation to take root.  With proper care, water is no more damaging to the rammed earth house than any other type of house.  Like concrete, rammed earth walls strengthen over time, but are strong enough upon completion to support a roof and to be inhabited.  Rammed earth houses exist and provide comfort at the sultry ecuador or in colder climates, such those climates of Canada, Russia and Scandinavia.  Its beauty cannot be denied.  

Take a minute, go to and search for "rammed earth."  You will be impressed by how pretty and grand it can be.  Here is a plantation house in South Carolina. 

Here is a really good example of what some modern designers have done with its aesthetic potential  

The labor involved with rammed earth is significant, and care must be taken in rammed earth design.  Through various field tests, you must make sure that the soil is the right composition of gravel, sand, silt and clay to ensure optimal densification.  Then, you must excavate and transport the soil to the building cite, where it must be sieved and mixed to the determined optimal-level of soil and moisture before it is placed in the formwork.  The formwork must be strong enough to withstand the immense force exerted on all its sides during the ramming process: rammed earth has a density of between 1800 and 2200 kg/m³, comparable to the density of sandstone, around 2400 kg/m³, so you are basically making sandstone.  Actually, because the primary aggregate of a rammed earth wall is sand, rammed earth walls resemble sandstone when completed.  Around 4"-5" of soil is placed in the formwork at a time, and this is compacted with a rammer to about half its volume.  In moist climates, the foundation of rammed earth must be elevated to between 1'-2' above the ground to prevent rain from splashing up from the ground and damaging the wall.  There is typically a bit more overhang on the eaves of rammed earth roofs than the roofs of other buildings to minimize its exposure to the rain.  The more curious of the readers are wondering about roofs and door and window openings.  Well, this is not a how-to blog.  Suffice it to say, extra care must be taken with the jambs, sills (only with windows) and lintels (load-bearing support beam above windows and doors) of windows and doors.  My goodness, that sort of sounded angry. 

Many of you are familiar with rammed earth structures.  A significant part of the Great Wall of China is made of rammed earth. Alhambra at Granada in Spain is made of rammed earth, or as it is called in Spanish, tapial
Many homes still inhabited near Lyon, France date back 600-900 years and are made of rammed earth, or as it is called in French, pisé de terre.   

There are, no doubt, doubters amongst you.  In his 1924 book, Karl Ellington wrote a bit about the skepticism he faced after years in the field:

"The fact that the pisé method is not known everywhere is by many taken as indicating or proving that pisé must have been tried and found wanting.  

But anyone who will give a little more attention to the subject will find, that in some parts of the world the pisé-method has been in use for several thousand years.  And in countries where the pisé-method has not been practiced it has never been tried because of the presence of wood or brick or other materials, -and tradition has cared for the continued use of methods once established, just as pisé has kept its ground from times remote and until the present day in localities where everyone knows the merits of the method and is familiar with the requirements in utilizing it.  

If it only was as easy to remove prejudice as to build with pisé, the method would be in use everywhere today."

Here a picture of a rammed earth building in Sweden from Mr. Ellington's book. 

It occurs to me that I could continue citing others interested in or involved with rammed earth (e.g., Thomas Jefferson, William Henry Harrison, Frank Lloyd Wright, etc.), defending it as a preferred construction method for residences and other buildings; however, I am too young in the process to defend it whole-heartedly:  thus far, my experience in rammed earth is limited to hours of research and a few hours of ramming earth in Auroville.  And while my research produced many great sources trumpeting the virtues of rammed earth, and ramming earth in Auroville produced a beautiful five foot wall, if I am honest with myself, I, too, am amongst the doubters.  I have not built anything substantial with it yet, have not experienced the process.   Which brings me back to the Boden-Haus.  

Robert and Rachel, a married couple who graduated from Davidson College, operate an organic farm in Greenville, Tennessee.  We were acquaintances in college, but our mutual friend Arthur put us into contact, as he was aware of my interest in rammed earth and their commitment to sustainable, healthy living.  They were gracious enough to invite me to build my first rammed earth building on their farm.  Rachel is a baker and is in need of a proper space in which she can do baking things.  So, this first building will be utilized as such.  

Here are some pictures from the ground-breaking ceremony.

                         The Site of the Boden-Haus                                     Rachel Breaking Ground

                 Robert Breaking Ground

                      Me Breaking Ground

Being German, We Gave Its Foundation Beer


The Boden-Haus is still in its early stages, and I now spend my days (when it's not raining) shoveling soil and sourcing stones, as we need 26 tons of each for the project.  Shoveling is harder work than one might think, unless one has done it, but it is really nice to be outside in beautiful Tennessee.  I will be updating this blog more often as work progresses.

I've also begun growing a chinstrap beard out and will continue to do so until the Boden-Haus is complete.  I hope to look like Solon Robinson, the inspiration for the beard.