Building with earthbags {sometimes called sandbags} isboth old and new. Sandbags have long been used, particularly by themilitary, for creating strong, protective barriers, or for floodcontrol. The same reasons that make them useful for these applicationscarry over to creating housing. Since the walls are so substantial,they resist all kinds of severe weather {or even bullets} and alsostand up to natural calamities such as earthquakes and floods. They canbe erected simply and quickly with readily available components, forvery little money.

Earthbag building fills aunique niche in the quest for sustainable architecture. The bags can befilled with local, natural materials, which lowers the embodied energycommonly associated with the manufacture and transportation of buildingmaterials. The fill material is generally of mineral composition and isnot subject to decomposition {even when damp}, attractive to vermin, orburnable...in other word it is extremely durable. The fill material isgenerally completely non-toxic and will not offgas noxious fumes intothe building.

Earthbags have the tremendousadvantage of providing either thermal mass or insulation, depending onwhat the bags are filled with. When filled with soil they providethermal mass, but when filled with lighter weight materials, such ascrushed volcanic stone, perlite, vermiculite, or rice hulls, theyprovide insulation. The bags can even act as natural non-wicking,somewhat insulated foundations when they are filled with gravel.

Becausethe earthbags can be stacked in a wide variety of shapes, includingdomes, they have the potential to virtually eliminate the need forcommon tensile materials in the structure, especially the wood andsteel often used for roofs. This not only saves more energy {andpollution}, but also helps save our forests, which are increasinglynecessary for sequestering carbon.

Anotheraspect of sustainability is found in the economy of this method. Thefill material can be literally "dirt cheap," especially if on-site soilis used. The earthbags themselves can often be purchased as misprintsor recycled grain sacks, but even when new are not particularlyexpensive. Burlap bags were traditionally used for this purpose, andthey work fine but are subject to rot. Polypropylene bags have superiorstrength and durability, as long as they are kept away from too muchsunlight. For permanent housing the bags should be covered with somekind of plaster for protection, but this plaster can also be earthenand not particularly costly. A few rolls of barbed wire to reinforcethe structure rounds out the primary expense for the wall system.

Theease and simplicity of building with earthbags should also bementioned, since there is much unskilled labor available around theworld that can be tapped for using this technology. One person familiarwith the basics of earthbag building can easily train others to assistin the erection of a building. This not only makes the process moreaffordable, but also more feasible in remote areas where many commonbuilding skills are not to be found.