As an architectural enthusiast, I have long admired Louis Khan. When I first visited San Diego years ago, I made sure to visit The Salk Institute. To see how concrete was used as both structure and frame, guiding my eyes toward the ocean. Kahn inspired me to dream about one day building a home made of concrete.
But then I began reading about the environmental impacts of cement production. I had grown up believing cement was a simple blend of sand, stone and lime. The truth is more complex, messy and corrupt. The production of cement requires baking in 1000-degree kilns and this heat (and the energy required to dig up and transport the ingredients) result in significant amounts of carbon. As noted in this BBC article: If the cement industry were a country, it would be the third largest emitter in the world — behind China and the US. Concrete production accounts for anywhere from 6% to 10% of all carbon emissions.
And concrete production is increasing globally. The world is now facing a sand shortage and emerging markets are suffering for it. In India, there is now a “sand mafia” that is literally stealing sand from poor villages. What is it about organized crime and cement?
So, needless to say, I’ve put away my concrete dreams. Fortunately, they have been replaced by dreams of a home built of earth, thanks in part to this monumental book, curated and edited by Jean Dethier, The Art of Earth Architecture: Past, Present, Future.
Raw earth has been used for nearly ten centuries as the basis for homes, villages, entire cities across all continents. A portion of China’s Great Wall. The Taos Pueblo, one of the oldest continuously inhabited communities in the United States. And, in Yemen, the old walled city of Shibam, a UNESCO World Heritage Site and a place I hope to one day visit.
Jean Dethier spent fifty years researching this book and it shows in the more than 250 sites profiled within, complete with full-color photographs and architectural renderings.
Raw-earth building has never really gone out of style, but it has never gone globally mainstream, despite its many advantages over concrete. The obstacles to the raw earth industry are many, beginning with the well-established concrete and steel industries, who rightly see this industry as a threat. And the fact that there is no “earth” lobby doesn’t help matters. There are also building codes that make raw earth contruction more expensive to pursue — not necessarily because these structures are less safe, just that they don’t easily conform to existing methods of measurement. The fact that there are 7-story structures standing in Shibam.
Paris produces 18 million tons of earth each year due to various construction projects, earth that is sent to landfills. India needs 40 million homes to accommodate its population. There are not enough trees, there is not enough sand to produce the concrete. But there is plenty of earth.
Contributor Martin Rauch, who has lived in a three-story rammed earth home for a decade, writes:
It is said that a third of the human race still lives in earth houses, but sadly this figure is falling day by day. If everybody lived in housing typical of industrialized countries, three planet Earths would barely be sufficient to provide all the materials necessary. In further industrializing construction worldwide, we are going down the wrong path. I am convinced that in three generations’ time, half of humanity will be living in comfortable earth buildings.
And as this book clearly shows, this ancient technology is as relevant today and even more so. And the results can be as striking as any building made of concrete, even one by Louis Kahn.
Consider the Tuscon office of architect Rick Joy, with walls built of rammed earth:
And this rural Australian multi-unit residential complex designed by Luigi Roselli, built out of the longest rammed earth wall south of the equator:
Or the mixed-use office Alnatura Campus in Germany, with walls of prefabricated rammed earth, designed by haas cook zemmrich:
As contributor Patrice Doat writes: The universal right to build out of earth requires nothing less than a cultural and educational revolution.
This book provides an inspiring step in that direction.