The expanded clay comes from the firing of various clays which are then ground into large-sized grinding wheels and reduced to a spherical granular material which is baked at very high temperatures giving rise to small spheres that retain humidity in the spheres. Due to its lightness and its qualities of retaining water, it is used in many constructions as thermal insulation and with it we obtain concretes suitable for the purpose. With it, other functions are also carried out in the construction field, such as the filling of underground tunnels through injections of the material into the subsoil or to fill retaining walls or to reinforce parts that had been built with poor material. Behind those spherical balls that we often see, there is a huge work by those who transform the clay. After extraction, it is left for several months in open-air quarries but, moreover, it resists even very humid external temperatures and is a material resistant to parasites. It is not fuel anyway, so there is no energy recycling.
The pros and cons of using expanded clay
As we have seen, this very light material is used for many things. Useful in attics, under floors, under any other walkable soil, where it is injected in bulk form. It is also injected into the concrete blocks, giving them an unusual lightness and thermal transmission. The manufacturers of outdoor furniture make continuous use of it to create the furnishings. But expanded clay also has its pros and cons. First of all, the quarries where the expanded clay is placed are in the open air and have a significant environmental impact, a condition contrary to ecological green building. When it is produced it has a large expenditure of energy and gases and lubricants are used which, if not properly filtered, would cause damage to the ecological system. On the other hand, one of the great advantages is that expanded clay is rot-proof, that is, resistant to insects and parasites. If any element made of this material catches fire, the expanded clay does not emit toxic fumes that could damage the environment and people. The clay is resistant to atmospheric agents and even if continuously exposed to conditions of adverse temperatures, its inalterability is highly guaranteed. In addition, nature has a lot of clay that can be found quietly. It is not of volcanic origin, therefore it does not emit harmful elements for the inhabitants of a certain area even if placed in a landfill. Its use is remarkable in the industries that produce garden fountains, outdoor and indoor fireplaces precisely because of the solid and long-lasting material.