What if you didn't need teams of bricklayers, shovels, excavators and concrete mixers to lift it, but a special 3D printer and the necessary equipment to extract the clods? It sounds crazy but that is, neither more nor less, the idea of the Institute of Advanced Architecture of Catalonia (IAAC). The world needs more sustainable houses and that's basically the concept behind the TOVA project.

To demonstrate that the proposal does not have to remain on paper and in the field of theory, the IAAC has developed, within the framework of its 3dPA Research Postgraduate Degree, an authentic construction made with clay. It is just a test, a small building of just five square meters (m2) built in the Valldaura Labs facilities of the IAAC as a test, but it aims to show the possibilities of the resource and, above all, mark a new path.

TOVA is—they say from the IAAC—the first building in Spain built with mud and a 3D printer. To give it shape, its creators used only a WASP crane, already designed for architectural work, and “kilometer zero” materials that were obtained in the environment itself. Nor was a large investment of time necessary: in seven weeks it was up and running.

“The construction process has not generated waste, since the materials were obtained within a 50-meter radius. The structure was made with local mud, mixed with additives and enzymes, to achieve the structural integrity and elasticity of the material necessary for optimized 3D printing,” says the Catalan institution. They used geopolymer in the foundation and wood was used in the roof. In order to guarantee its durability, a waterproof layer made from raw materials as basic as aloe or egg white was added.

When designing it, the experts have also taken into account the climatic conditions that the construction will face in the Mediterranean, with a structure adapted to both the cold of winter and the high temperatures of the summer months. One of the keys to the design is the network of cavities that make up the walls, which prevents heat loss and protects from the sun.

Those responsible emphasize the advantages of the construction: they ensure that its carbon footprint is almost zero and no waste is generated. “Current construction methods are responsible for 36% of CO2 emissions, TOVA is a pioneering example of low-carbon building.”

TOVA aims to be in any case a starting point, “the beginning” of a broader collaboration with WASP to – the IAAC details – end up building an entire house with 3D printing. In its favor it has the “infinite possible applications” of the construction model, suitable, they say, for building everything from homes to infrastructure in indoor or outdoor public spaces.

The combination offers some interesting advantages, such as the simplicity of the process, which saves, for example, the logistics involved in transporting materials, its low cost, how versatile the process is, its low contaminating footprint or the ease of managing the remains once the building fulfills its mission and useful life. The scarcity of manpower and resources that it implies also makes it an interesting idea for emergency situations in which it is urgent to enable residences quickly and easily.