Adobe

Cal-Earth polypropylene tubes being used to construct domed structures. By DVIDSHUB CC BY 2.0 (http://creativecommons.org/licenses/by/2.0), via Wikimedia Commons

The notion of building walls with sandbags or earthbags has been around at least 100 years.^[1] Originally and into modern times these have tended to be burlap (hessian) fabric bags forming temporary structures acting as flood barriers or as military fortifications. It is unclear exactly when the first time this was done,^[2] but there is some evidence that in military settings sandbag walls were being used prior to World War I. Indeed, some WWI trenches reinforced with oil impregnated sacks still survive, despite being intended to be temporary.^[2]

Building permanent structures such as homes using earthbags is a more recent development.^[1] Otto Frei experimented with earthbag building in the in 1960s in Germany.^[3] In the 1970s, again in Germany, Gernot Minke and others at the Research Laboratory for Experimental Building at Kassel Polytechnic College were investigating ways of building earthquake resistant structures without cement. They used polyester and burlap tubes filled with pumice to make domed structures. With the Francisco Marroquin University in Guatemala and the Centro de Estudios Mesoamericano Sobre Tecnologia Apropiada (CEMAT) a structure was built in Guatemala in 1978 out of lime soaked cotton fabric bags filled with pumice sand.^[4]

The Earthbag building method was popularized by Persian Architect Nader Khalili who eventually developed a building technique he termed Superadobe, where polypropylene bags or tubes filled with moistened adobe soil were used to form often domed structures. Khalili went on to publish 6 books and found the non profit organization Cal-Earth Institute (California Institute of Earth Architecture) in 1981.^[5] He has been criticized for claiming his superadobe technique was "freely put at the service of humanity and the environment" at the same time as attempting to patent earthbag building techniques in very general terms in 1991. It is claimed he requested that all other promoters of earthbag building enter into a contract with him to continue their work.^[1]

The Quake Safe is a method of making adobe houses safer in earthquakes. It is a frame made from string, bamboo (or other available wood; ie eucalyptus, ...) and wire. It can be retrofitted to an existing adobe (mud brick) house or incorporated into a new house as it's being built.

The main idea is to have poles inside and outside the walls, with string (or wire?) connecting the inside and outside poles, through small holes in the wall. Wire then runs horizontally at several levels between all the inside poles, and between all the outside poles. This connects them and provides basic physical support if they walls start to collapse.

This design gives the house a much higher level of protection against earthquakes. It is not designed to prevent the house from being seriously damaged or destroyed, but rather to prevent complete collapse. At the very least, it can be expected to give more time for the occupants to escape from the building.