Build cities out of dirt

  Earth buildings are warm in winter and cool in summer, protecting them from extreme weather. In the search for sustainable architecture, architects have rediscovered this historic but long-neglected building.
  Dirt skyscrapers soar into the sky in the ancient city of Sanaa, Yemen. Built entirely of mud, the structures are decorated with striking geometric patterns that blend in with the surrounding ocher-colored mountains. The mud architecture of the ancient city of Sana’a is unique and has been included in the World Cultural Heritage List.
  UNESCO describes the ancient city of Sana’a in this way: “This is a very unique architectural complex that reflects the characteristics of the early Islamic space organization. These buildings use local materials and show superb skills.”
  Yemen Davao Anni Although the buildings are thousands of years old, they look very modern, said Salma Damluj, founder of the Brick Building Foundation and author of “Yemeni Architecture and Its Reconstruction.” Most of these ancient buildings are private residences, and people still live in them.
  The reasons for the appeal of these mud structures are obvious: they insulate well, are reusable, and are remarkably adaptable to the demands of modern life, Damluj said. “This is a kind of architecture of the future,” she said.
  Architects around the world are researching sustainable buildings that can withstand extreme weather such as floods and heat, and mud buildings have re-entered their vision. Will this ancient architectural form influence the design of future cities and homes? Can this back-to-basics architectural technique tackle the climate crisis?
  | Climate Issues in Construction | The
  construction sector is responsible for 38% of global CO2 emissions. The construction industry will have to make major changes if it is to meet the 2050 global goal of carbon neutrality and limit the rise in global temperatures to 1.5 degrees Celsius.
  Scientists warn that achieving these goals will require replacing concrete with less polluting building materials. Concrete is the protagonist of the modern construction industry, and the production process emits a lot of greenhouse gases. Concrete buildings are responsible for 7% of global carbon dioxide emissions, much higher than the aviation industry’s 2.5%. About 4 billion tons of cement, the main component of concrete, are produced worldwide each year.
  “We can no longer live in these concrete forests,” Damluj said. “We need to think about the surrounding environment and biodiversity, not just ourselves.”
  Damluj believes that soil can be a perfect substitute for concrete. Earth construction has a low environmental impact and the earth itself can be reused.
  | Reviving an Ancient Tradition |
  The ancient city of Djenné in Mali is located in the Niger Delta region and was founded in 800 AD. It used to be an important place for merchants trading between the Sahara and Sudan. Djenne is famous for its earthen architecture, especially the Great Mosque of Djenne – the world’s largest earthen structure, 20 meters high, sitting on a 91-meter-long platform.
  Under the guidance of professional masons, the residents of Djenné work together to renovate the mosque every year. Trevor Marchand, emeritus professor of social anthropology at SOAS, University of London, and author of The Masons of Djenné, said: “These master builders are beloved by Malians because of their skill and ability to protect The mud building and the people inside it.” The restoration work is an expression of social cohesion. “Everyone is involved, the children with the mud, the women carrying the water, the masons to guide,” he says.
  Djenné’s mud structures are constantly changing as residents repair and rebuild them. “There is an extraordinary vitality to this kind of building,” said Marchand. “The soil is very malleable, and people can adjust and transform the building at any time according to the changes in the family size.” If the family size increases, people can easily add more rooms; and if the population dwindles, the superfluous rooms are left to crumble and return to dust.
  | Sustainable Architecture |
  Historic mud buildings are now a source of inspiration for contemporary architects. Serbian architect Dragana Kozičić specializes in mud construction.
  ”Our ancestors were very smart and they came up with practical solutions – they used local materials,” Kozičić said. “Dirt is everywhere and can be used to build anything, such as walls, floors, ceilings, stoves. , even roofs.”
  Kozičić trained at the Center for the Study and Application of Earth Architecture and is now in Serbia repairing and building mud houses, reviving this age-old building technique.
  ”Soil is contagious, and you will fall in love with it as soon as you touch it once.” Kozicic said, “You don’t need to take any protective measures, just play with it.”
  Anna Hellinger is an Austrian architect She is a teacher who uses natural materials such as mud and bamboo to build houses, and she agrees with this point of view. “It’s a great experience to touch the dirt. You don’t need any tools, you can do it with your hands,” she said.

  Hellinger has been using clay to build houses for nearly 20 years, and has designed many very famous clay buildings, such as the Modern Education and Training Institute in Rudrapur, Bangladesh, for which Hellinger won the Aga Khan Award for Architecture in 2007. She said: “Mud is a very universal material. Whether poor or rich, people can use mud to build houses.
  ” Finished by local artisans and students.
  ”The architect used lighter materials such as bamboo strips and nylon ropes to connect soil-derived materials such as loam and hay to form the structure of the building, which provides ideas for the sustainable development of the construction industry and is a model.” Aka The judges of the Khan Architecture Prize commented on the Modern Education and Training Institute.
  “Dirt is a really sustainable building material,” says Hellinger. “Dirt can be reused over and over without consuming any energy. In fact, it gets better and better the more you use it. And , the soil is like dough, which is very easy to adjust during the construction process.”

  However, the construction of mud buildings should also follow the concept of sustainable development, and should not encroach on the cultivated land. The global population is expected to reach 9.7 billion in 2050, putting enormous pressure on land use.
  | Healthy, Resilient Buildings |
  Architects believe that one of the properties of clay buildings is that they are warm in winter and cool in summer. The high thermal mass of the earth walls absorbs and stores heat slowly, preventing the interior from becoming overheated.
  ”The earth wall absorbs heat from solar radiation during the day and then releases it at night. The indoor temperature will be maintained at a very comfortable level without too much fluctuation.” American architect and head of “Building Restoration Studio” Pa Meera Jerome said. Therefore, mud buildings can reduce the frequency of air-conditioning use and reduce related greenhouse gas emissions.
  A 2021 report by the UK Environmental Review Board recommends that people use “recyclable, bio-based, breathable” materials such as clay, lime-based plaster and natural fibers to improve insulation in existing buildings. hot sex.
  ”Compared to concrete or corrugated metal buildings, mud buildings can keep the room temperature at a relatively stable level, so residents will have a more comfortable experience.” Marchand said, “Another advantage is that the thick mud brick walls can also It blocks out noise from the outside or neighbors.”
  In addition, the dirt can “breathe,” which has other benefits. The porous structure of soil allows moisture to enter the house, improving the air quality indoors. “Dirt absorbs excess moisture from the air and releases it when needed, which is why we say mud buildings can ‘breathe’,” Kozičić said.
  ”Mud buildings are very healthy buildings that can ‘breathe’ like humans and have a ‘skin’ that can adapt to different temperatures,” Damluj said. “A clay building is very similar to our body.”
  In addition, mud buildings are quite strong and can handle extreme weather such as heat waves, floods, and droughts. Scientists believe that as temperatures continue to rise, so will the frequency and intensity of extreme weather. The United Nations Intergovernmental Panel on Climate Change warned in a report last year that most human settlements are ill equipped to cope with extreme climate events. Avoiding damage from such events and protecting residents requires building buildings and infrastructure that can handle extreme weather.
  Earth buildings can withstand extreme events such as earthquakes and high winds. “Because this kind of construction can distribute the pressure on the surface, and concrete and cement can’t.” Damluji said. However, it also depends on the strength of the seismic waves and what kind of soil the earth building is built on, Jerome said.
  ”The earth buildings are coated with several layers of earth, ashes, lime and stucco on the outside to keep out moisture and thus resist monsoon rains and floods,” said Damluj.
  According to Jerome, the impact of flooding on mud buildings depends on whether the building is located in a floodplain and has solid foundations. In 2008, the Hadramawt province in eastern Yemen experienced severe floods that damaged 5,000 mud buildings. These buildings were built in floodplains with no or weak foundations. In the nearby Dhawan Valley in the desert canyon region, flood damage was far less severe, as the mud structures there had foundations 1.5 meters or deeper and were made of dry stone.
  Jerome added: “The roads in the canyon have been built in the form of breakwaters, which can channel the flood water into the irrigation canals of the date palms. Only 25 buildings in the Dhawan Valley have been affected by the flood.” For a modern and comfortable home, consider earth construction. “Mud building is very adaptable. If you want to knock out a wall or change the design of the house, you can recycle all the materials,” Damluj said.
  Overall, mud building is very mature and repeatable . Take advantage of. “The mud building is very comfortable, and you can always renovate and re-wire and re-pipe.”