There raw earth it is a green building material with excellent bioecological and constructive characteristics. It is also an ancient material. Currently, about a third of the world's buildings are made up ofconstructions in raw earth: many of these are found in Africa, but are also widespread in Europe and Central America where there are examples of considerable size.
What is the raw earth? The composition changes depending on the place of extraction, but the most common 'ingredients' are clays mixed with silt and sand. The structure and consequently the physical characteristics change according to the particle size of the components.
In any case the raw earth it is an abundant and recyclable material and its non-polluting use has a low overall energy impact. This makes it an excellent green building material.
The construction elements in raw earth, blocks or bricks, can be made of pure pressed earth or together with other light materials (usually straw, shavings and perlite) which greatly improve the thermal insulation properties.
With elements in raw earth building components can be made (especially internal and external walls, dividing and load-bearing walls) which are breathable, hygroscopic, resistant, with good structural capacity and free from static electricity accumulation phenomena. Usually, when components are built with good quality earths, they are also free from harmful emissions.
There raw earth, due to its characteristics, it is also suitable for the construction of multi-storey buildings, where it helps to create a healthy and comfortable microclimate. Thermal insulation and hygrometric balance are the strengths of this material.
How is it built in raw earth? Here we enter a discourse that starts from afar because the raw earth it is an ancient material and the construction systems are also ancient. There are several techniques (the best known are called adobe, pisé, bauge and faconnage) which can vary in consideration of the characteristics of the land used.