7292019 Earth - A Building Material of the Future

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earth - a building material of the future

some of the oldest buildings on the planet are made of earth currently it is estimated that onehalf of the worlds population - approximately three billion people on six continents - lives or worksin buildings constructed of earth

earth is a 100 eco-friendly building material it is neither manufactured nor transporteda wall made from raw earth serves as a natural air conditioner being warm in winter and cool in summerwhen the building is demolished the earth returns to the soil and can be recycled indefinitely

largely shunned since the arrival of its close cousin concrete in the 1950s earth is now back infashion as its ecological and aesthetic benefits attract the attention of an increasing numbers of contemporary architects and eco-builders industrial sectors devoted to earthen building arecurrently emerging as this sustainable material wins over

the misconceptions associated with earth architecture is that many assume its only used for housing inpoor rural areas - but there are examples of airports embassies hospitals museums and factories that aremade of earth current research efforts are focused on increasing its resistance and processing speedin order to make it a modern and competitive material

ma terre premiegravere pour construire demain (earth today for construction tomorrow)

ma terre premiegravere pour construire demainis an exhibition on earth raw as a building material as itpertains to environmental economic and aesthetic of today and tomorrowthe exhibition was produced in collaboration with the research laboratory of the ecole nationale supeacuterieuredarchitecture de grenoble craterre ma terre premiegravere pour construire demain is co-produced withfour regional agencies as the host in turn until 2013 the flying strasbourg the science forum villeneuvedascq the pont du gard and confluence museum in lyon

the exhibition is divided into 4 main sectorsearth is made up of grainsexperiments with earthbuilding with earthbuilding with grains tomorrow

unbaked earth -earth is a raw material which man has used for thousands of years to build houses and from which couldarise ways to develop alternatives to industrial materials like cement

for building purposes it is preferable to have a solid material but for the implementation phasea fluid material is best grains possess both of these propertiesin construction gaps always represent a weakness this is why every effort is made to stack grains

within materials in a as compact manner as possibleearth is a natural concrete it is composed of billions and billions of grains which bind together thanks to water the resulting clay is always surrounded by a thin layer of water molecules whichit captures in the atmosphere a clay wall is never dry even in the desertfurthermore clay is electrically charged and creates electrostatic f orces which increase the adhesivepower of the grains

a view into the exhibition earths color image copy designboom

where does earths color come fromiron oxides mix with clay to give it this highly variable coloring ear th can vary greatly includingwithin the same country for example in the urban environment building earth is usually pollutedby debris from former brick and concrete constructionsforest earth is black because it contains a high proportion of organic materialalso this earth is not suitable for construction

a view into the exhibition granulometry techniqueimage copy designboom

earth is made up of grainsthat are classified according to their size the granulometry technique defines them as followscoarse diameter of 2 to 20 cmgravelly diameter of 2 mm to 2 cmsandy diameter of 60 microns to 2 mm

silty diameter of 2 microns to 60 micronsclayey below 2 microns

earth is a ready building material which requires little further processingwhen clay is mixed with water it becomes malleable plastic or liquid allowing it to be shapedwhen drying clay sets and recovers its cohesive properties and so can bind the soil togetherclayey earth should be free of stones and gravel a high proportion of sand reduces the risk of crackingunusable earth contains insufficient quantities of clay which is essential for building since it acts as cementto obtain a good building material which is strong and easy to use the proportion of clay in a soil shouldbe about 15 per cent on average the sand should be 40 to 80 per cent the gravel 0 to 40 per cent and thesilt 10 to 25 per cent if the clay content in a soil is too high some minerals such as sand and gravelsor fibres such as straw or hair can be addedgenerally a fairly wet mix with higher proportions of clay is used in mouldings and spreading applicationswhile a mix with less clay is best suited to compaction in a moist or damp state

buildings of unstabilised earth face the risk of erosionunless special design precautions are taken to reduce exposure to rain and moisturefor durability earth should only be used where it is not prone to water or dampoptimum designs will depend a lot on the environment such as the natural drainage and water table the climatefor example rainfall (quantity and intensity) and winds during rains and on the maintenance practices of the usersstabilizers and other additives or methods such as good compaction and grain size optimisation can reduceswelling shrinkage and cracking increasing strength and water resistance

principle techniques of building using unbaked earth

the four main techniques traditionally used around the world for building with earth are piseacute or rammed-earthdaub adobe and cob adobe rammed-earth and compressed earth blocks are the most widespread earthconstruction techniques used today

- rammed earth the granulometric composition of this earth makes it possible to obtain a highly resistant materialimage copy designboom

piseacute or rammed earthis a mixture of earth sand or gravel and clay which is kneaded and then compactedthe earth has to be packed down using a rammer this pressure is deviated towards the side walls of the formwork which can split meaning certain precautions must be takenif a layer of earth is too thick it is not properly packed down the pressure of the rammer is not reachingthe grains at the bottom a rammed-earth wall therefore corresponds to thin layers of packed earthwhich are overlaid

7292019 Earth - A Building Material of the Future

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a view into the exhibitionimage copy designboom

the great mosque of djenneacute in mali a UNESCO world heritage site is one of the largest earth buildings in the world

see the making

A woman builds a house with her own hands from Peter Meier on Vimeo

a woman constructing her house all by her own she also produces the bricks out of clay by herselfvideo copy peter meier

- cob erath consisting in shaping lumps of clayey earth and stacking them up to form wallsimage copy designboom

cobis an ancient building techniqueballs of earth are stacked on top of one another and lightly tapped with hands or feet toform monolithic walls the earth is reinforced by the addition of fibres usually straw fromvarious types of cereal or other kinds of vegetable fibre such as grass and twigs

a view into the exhibitionimage copy designboom

built entirely by hand the greniers du sahel cold rooms measure up to 6 metres in height

see the making video

exhibition catalogue

bacirctir en terre by romain anger and laetitia fontaine was published as part of the exhibitionma terre premiegravere pour construire demain (earth today for construction tomorrow)the book presents the unique heritage of earth construction from the mythical shibam in yementhe manhattan of the desert - to the strange group of hakka houses in chinathe book includes projects from europe and documents the achievements of contemporary architectsand offers simple and fun experiments to understand the physio-chemical properties of earthpublished by httpwwweditions-belincomfrench language only

---more info on earth architecture

craterre-ensag the center for the research and application of earth architecture is part of the school of architectureof grenoble france

httpwwweartharchitectureorg

terra brasil 2010the third annual brazilian congress on architecture and earth building also known as terrabrasil 2010will take place in the city of campo grande in the state of mato grosso do sul (ms) brazil fromaugust 31st to the september 3rd 2010 the congress is being organized by the structural and civilengineering department (decccet) of the federal university of mato grosso do sul in partnershipwith the terrabrasil network (rede terrabrasil)