Superadobe is a form of
earthbag construction
Earthbag construction is an inexpensive building method using mostly local soil to create structures which are both strong and can be quickly built.
Earthbag development
Features
It is also natural building technique developed from historic mi ...
that was developed by Iranian architect
Nader Khalili
Nader Khalili ( fa, نادر خلیلی; 1936–2008) was an Iranian-born American architect, author, and educator. He is best known for his inventive structures that incorporated a range of atypical building materials to provide shelter in the d ...
. The technique uses layered long fabric tubes or bags filled with
adobe
Adobe ( ; ) is a building material made from earth and organic materials. is Spanish for ''mudbrick''. In some English-speaking regions of Spanish heritage, such as the Southwestern United States, the term is used to refer to any kind of e ...
to form a compression structure.
The resulting
beehive
A beehive is an enclosed structure in which some honey bee species of the subgenus '' Apis'' live and raise their young. Though the word ''beehive'' is commonly used to describe the nest of any bee colony, scientific and professional literature ...
-shaped structures employ
corbelled arch
A corbel arch (or corbeled / corbelled arch) is an arch-like construction method that uses the architectural technique of corbeling to span a space or void in a structure, such as an entranceway in a wall or as the span of a bridge. A corbel vaul ...
es,
corbelled domes, and vaults to create sturdy single and double-curved shells. It has received growing interest for the past two decades in the
natural building
A natural building involves a range of building systems and materials that place major emphasis on sustainability. Ways of achieving sustainability through natural building focus on durability and the use of minimally processed, plentiful or renew ...
and
sustainability
Specific definitions of sustainability are difficult to agree on and have varied in the literature and over time. The concept of sustainability can be used to guide decisions at the global, national, and individual levels (e.g. sustainable livi ...
movements.
History
Although it is not known exactly how long, Earthbag shelters have been used for decades, primarily as implements of refuge in times of war. Military infantrymen have used sand filled sacks to create bunkers and barriers for protection prior to
World War I
World War I (28 July 1914 11 November 1918), often abbreviated as WWI, was one of the deadliest global conflicts in history. Belligerents included much of Europe, the Russian Empire, the United States, and the Ottoman Empire, with fightin ...
. In the last century other earthbag buildings have undergone extensive research and are slowly beginning to gain worldwide recognition as a plausible solution to provide affordable housing.
German architect
Frei Otto
Frei Paul Otto (; 31 May 1925 – 9 March 2015) was a German architect and structural engineer noted for his use of lightweight structures, in particular tensile and membrane structures, including the roof of the Olympic Stadium in Munich for ...
is said to have experimented with earthbags, as is more recently Gernot Minke. It was
Nader Khalili
Nader Khalili ( fa, نادر خلیلی; 1936–2008) was an Iranian-born American architect, author, and educator. He is best known for his inventive structures that incorporated a range of atypical building materials to provide shelter in the d ...
who popularized earthbag construction. Initially in 1984 in response to a
NASA
The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research.
NASA was established in 1958, succeeding t ...
call for housing designs for future human settlements on the
Moon
The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width of ...
and on
Mars
Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System, only being larger than Mercury (planet), Mercury. In the English language, Mars is named for the Mars (mythology), Roman god of war. Mars is a terr ...
, he proposed to use
moon dust
Lunar soil is the fine fraction of the regolith found on the surface of the Moon. Its properties can differ significantly from those of terrestrial soil. The physical properties of lunar soil are primarily the result of mechanical disintegra ...
to fill the plastic Superadobe tubes and
velcro
Velcro, officially known as Velcro IP Holdings LLC and trading as Velcro Companies, is a British privately held company, founded by Swiss electrical engineer George de Mestral in the 1950s. It is the original manufacturer of hook-and-loop fasten ...
together the layers (instead of barbed wire). He came to term his particular technique of earthbag construction "Superadobe". Some projects have been done using bags as low-tech foundations for
straw-bale construction
Straw-bale construction is a building method that uses bales of straw (commonly wheat, rice, rye and oats straw) as structural elements, building insulation, or both. This construction method is commonly used in natural building or "brown" cons ...
. They can be covered in a waterproof membrane to keep the straw dry.
In 1995, 15
refugee shelters were built in Iran, by Nader Khalili and the
United Nations Development Programme
The United Nations Development Programme (UNDP)french: Programme des Nations unies pour le développement, PNUD is a United Nations agency tasked with helping countries eliminate poverty and achieve sustainable economic growth and human dev ...
(UNDP) and the
United Nations High Commissioner for Refugees
The United Nations High Commissioner for Refugees (UNHCR) is a United Nations agency mandated to aid and protect refugees, forcibly displaced communities, and stateless people, and to assist in their voluntary repatriation, local integrati ...
(UNHCR) in response to
refugees
A refugee, conventionally speaking, is a displaced person who has crossed national borders and who cannot or is unwilling to return home due to well-founded fear of persecution. from the
Persian Gulf War
The Gulf War was a 1990–1991 armed campaign waged by a 35-country military coalition in response to the Iraqi invasion of Kuwait. Spearheaded by the United States, the coalition's efforts against Iraq were carried out in two key phases: ...
. According to Khalili the cluster of 15 domes that was built could have been repeated by the thousands. The government dismantled the camp a few years later.
Since then, the Superadobe Method has been put to use in Canada, Mexico, Brazil, Belize, Costa Rica, Chile, Iran, India, Russia, Mali, and Thailand, as well as in the U.S.
While Superadobe constructions have generally been limited to approximately 4 meters in diameter, larger structures have been created by grouping several "beehives" together to form a network of domes. There is a 32′ (10m) dome being constructed in the San Ignacio area of Belize, which when finished will be the center dome of an eco-resort complex.
BBC News reported in March 2019 that superadobe structures have withstood earthquakes as severe as 7.2 magnitude.
Methodology
Superadobe's earthbag technique lends itself to a wide range of materials.
Polypropylene
Polypropylene (PP), also known as polypropene, is a thermoplastic polymer used in a wide variety of applications. It is produced via chain-growth polymerization from the monomer propylene.
Polypropylene
belongs to the group of polyolefins and ...
tubing is ideal, although
burlap
Hessian (, ), burlap in the United States and Canada, or crocus in Jamaica and the wider Caribbean, is a woven fabric usually made from skin of the jute plant or sisal fibres, which may be combined with other vegetable fibres to make rope, nets, ...
is also sufficient. Likewise, while sand, cement or lime are preferred, virtually any fill material (e.g. gravel, crushed volcanic rock or rice hulls) will work.
After materials are gathered and the dimensions of the building are decided upon, a circular foundation trench is dug, approximately 1 foot deep and 8–14 feet in diameter, giving room for at least two layers of earthbags to be laid down underground. A chain is anchored to the ground in the center of the circle and used as a pair of compasses to trace the shape of the base. Another chain is fastened just outside the dome wall: this is the fixed or height guide and provides an interior measurement for the layers as they corbel higher, ensuring the accuracy of each new layer as it is laid and tamped.
Between layers of tamped, filled tubes, loop of barbed wire functions as mortar and holds the structure together. Window voids can be placed in several ways: either by rolling the filled tube back on itself around a circular plug (forming an arched header) or by sawing out a Gothic or pointed arch void after the filler material has set.
Once the corbelled dome is complete, it can be covered in several different kinds of exterior treatments, both for aesthetic reasons and to protect the structure from environmental damage such as that from
ultraviolet radiation
Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nm (with a corresponding frequency around 30 PHz) to 400 nm (750 THz), shorter than that of visible light, but longer than X-rays. UV radiation i ...
. Like the materials for the construction itself, there are multiple choices. While CalEarth names plaster as the most common finishing option, soil and living grass have also been used. Khalili has also used a mix of earth and plaster, further covered by a "reptile" layer of cement and earth balls that strengthen the finish by redirecting stress.
Emergency shelters
According to Khalili's website, in an emergency, impermanent shelters can be built with unskilled labor, using only dirt with no cement or lime, and for the sake of speed of construction, windows can be punched out later due to the strength of the compressive nature of the dome/beehive. Superadobe is not an exact art and similar materials may be substituted if the most ideal ones are not readily available. Ordinary sand bags can also be used to form the dome if no Superadobe tubes can be procured; this in fact was how the original design was developed.
In an interview with an AIA (
American Institute of Architects
The American Institute of Architects (AIA) is a professional organization for architects in the United States. Headquartered in Washington, D.C., the AIA offers education, government advocacy, community redevelopment, and public outreach to su ...
) representative, Nader Khalili, Superadobe's founder and figurehead, said this about the emergency shelter aspects of Superadobe:
Bibliography
*
Khalili, Nader. "Nader Khalili." Cal-Earth. 19 Jan. 200
*Katauskas, Ted. "Dirt-Cheap Houses from Elemental Materials." ''
Architecture Week
''ArchitectureWeek'' is an international weekly magazine covering architecture and design, published online by Artifice, Inc. in Eugene, Oregon, United States. ''ArchitectureWeek'' was founded in May 2000, with its first issue publication on May ...
''. Aug. 1998. 19 Jan. 200
*Husain, Yasha. "Space-Friendly Architecture: Meet Nader Khalili."
Space.com
Space.com is an online publication focused on space exploration, astronomy, skywatching and entertainment, with editorial teams based in the United States and United Kingdom. The website offers live coverage of space missions, astronomical discov ...
. 17 Nov. 2000. 19 Jan. 200
*
Cameron Sinclair, Sinclair, Cameron, and Kate Stohr. "SuperAdobe." Design Like You Give a Damn. Ed. Diana Murphy, Adrian Crabbs, and Cory Reynolds. New York: Distributed Art Publishers, Inc., 2006. 104–13.
*Kellogg, Stuart, and James Quigg. "Good Earth." Daily Press. 18 Dec. 2005.
*Freedom Communications, Inc. 22 Jan. 200
*''Alternative Construction: Contemporary Natural Building Methods''. Ed. Lynne Elizabeth and Cassandra Adams. New York: John Wiley & Sons, Inc., 2000.
*
Kaki Hunter, Hunter, Kaki, and Donald Kiffmeyer.
Earthbag Building'. Gabriola Island, BC: New Society Publishers, 2004.
*Kennedy, Joseph F. "Building With Earthbags." Natural Building Colloquium. NetWorks Productions. 14 Feb. 200
*Aga Khan Development Network. "The Aga Khan Award for Architecture 2004." Sandbag Shelter Prototypes, various locations. 14 Feb. 200
*The Green Building Program. "Earth Construction." Sustainable Building Sourcebook. 2006. 14 Feb. 200
*NBRC. "NBRC Misc. Photos." NBRC: Other Super Adobe Buildings. 10 Dec. 1997. 14 Feb. 200
*CCD. "CS05__Cal-Earth SuperAdobe." Combating Crisis with Design. 20 Sept. 2006. 14 Feb. 200
*American Institute of Architects. A Conversation with Nader Khalili. 2004. 14 Feb. 200
*New York Times. When Shelter is made from the Earth's Own Dust. 15 Apr 199
See also
*
Earthbag construction
Earthbag construction is an inexpensive building method using mostly local soil to create structures which are both strong and can be quickly built.
Earthbag development
Features
It is also natural building technique developed from historic mi ...
References
{{reflist
External links
- www.videterra.org, Superadobe Italia, sharing information and promoting superadobe domes and houses. Vide Terra provides superadobe workshops in Italy, Europe and the Mediterranean area.
Khalili's site describing his explanation of his method which he names "Superadobe", not "Super Adobe".
earthbagbuilding.com- Includes many photos of Superadobe projects.
calearth-superadobe
Masonry
Appropriate technology
Soil-based building materials
Foundations (buildings and structures)