Rammed Earth Technology

1. Rammed earth is an ancient building method that has seen a revival in recent years as people seek more sustainable building materials and natural building methods. Because of the nature of the materials used it is incombustible, thermally insulating and very strong and hardwearing. It also has the added advantage of being a simple way to construct walls.
2. Traditionally, rammed earth buildings are common in arid regions where wood is in scarce supply. Using it involves a process of compressing a damp mixture of earth that has suitable proportions of sand, gravel and clay (sometimes with an added stabilizer) into an externally supported frame that molds the shape of a wall section creating a solid wall of earth. When the process is complete it is much like constructing a hand made wall of solid rock. Rammed earth has been used around the globe for millennia in a wide range of climatic conditions, from wet northern Europe to dry regions in Africa.
3. Evidence of the early use of rammed earth as been seen in Neolithic archaeological sites of the Yangshao culture and the Longshan culture in China along the Yellow River dating back to 5000 BCE. By 2000 BCE, the use of rammed earth architectural techniques was commonly used for walls and foundations in China. Because rammed earth structures utilize locally available materials, they typically have a low embodied energy rating and generate very little waste.
4. Earth used for building is a widely-available resource and harvesting it for use in construction has minimal environmental impact. Properly-built rammed earth can withstand loads for thousands of years as the history of rammed earth structures around the world has proven. Rammed earth is not only an economically viable construction technique; it results in pleasant, energy-efficient buildings.
5. Rammed earth is a green material for a number of reasons. It does provide good thermal mass, which implies good heat storage and absorption. It also controls humidity where walls contain clay which is exposed to an internal space.
6. Compressed Earth Block often referred to simply as CEB, is a type of manufactured construction material formed in a mechanical press that forms an appropriate mix of dirt, non-expansive clay, and an aggregate into a compressed block. The advantages of CEB are in the wait time for material, the elimination of shipping cost, the low moisture content, and the uniformity of the block thereby minimizing, if not eliminating the use of mortar and decreasing both the labor and materials costs.