TECLA is a prototype house printed from raw earth in Massa Lombarda, near Ravenna in northern Italy. It was designed by Mario Cucinella Architects and printed by WASP, an Italian 3D-printing company, using soil dug close to the site. The printing took about 200 hours, and the finished house, two connected dome-shaped rooms with ribbed clay walls, was unveiled in spring 2021. It is a single experimental home rather than a village, but it was built to show how a low-carbon dwelling could be made almost anywhere from local earth.
Here is how TECLA was made, what makes it different from both conventional houses and other 3D-printed buildings, and what questions it still has to answer.
Who built TECLA, and why
The project brought together two partners. Mario Cucinella Architects, a Bologna practice known for sustainable design, was responsible for the architecture. WASP, short for World's Advanced Saving Project, handled the engineering and printing. WASP, based in Massa Lombarda, has been developing construction printers since 2012, and its founders took inspiration from potter wasps, insects that build nests from mud.
The design grew out of research at SOS – School of Sustainability, a school founded by Cucinella that combines teaching, research and practice. Working with master's students from the Sustainable Environmental Design programme at the Architectural Association in London, the team studied the causes of homelessness and housing shortages and how technology could help in very different climates. The aim was a shell that could be adapted to hot or cold regions while using little energy.
The name works on two levels. The architects linked it to Tecla, one of the imaginary cities in Italo Calvino's book Invisible Cities, a place that is always under construction. WASP also presents it as a contraction of "technology and clay".
How the house was printed
WASP used its Crane WASP system, a modular printer that can be assembled on site. Each unit covers a printing area of about 50 square metres, and several units can work together. For TECLA, two printing arms were synchronised to work on the same structure at the same time, which WASP described as a first for a construction project.
The figures are striking for a house:
- About 60 cubic metres of natural material, mostly earth from the local area.
- 350 printed layers, each 12 millimetres thick.
- Around 200 hours of printing in total.
- An average electricity draw below 6 kilowatts, according to WASP.
Planning approval came in May 2019 and printing started that September. Final installation took longer than the original early-2020 target, and the house was presented in spring 2021.
WASP's video shows the twin printing arms laying down clay layer by layer, and the ribbed domes slowly rising from the ground.
What the walls are made of
Earth is one of the oldest building materials in the world. Rammed earth, cob and adobe are still used across Africa, Asia, the Middle East and southern Europe. TECLA adapts that tradition to a machine. The building company Mapei helped refine the clay mix so it could be extruded and still hold its shape, and RiceHouse, which makes building materials from farm waste, supplied rice husk and straw to improve the insulation of the envelope.
The ribbed, hollow walls do several jobs at once. Their shape gives stiffness without steel reinforcement, the cavities can be filled with insulating material, and the curve of the domes sheds rain. Because the material is unfired clay, the shell can in principle be broken down and returned to the ground, or wetted and reused, at the end of its life. The designers describe it as close to zero-waste.
Why 3D printing with earth matters
Construction is a major source of emissions, largely because of cement and steel. Producing cement alone accounts for several percent of global carbon dioxide emissions. Using raw local earth avoids most of that, and printing on site reduces transport, formwork and waste.
There is also a social argument. In 2017 the United Nations projected that the world population could reach 11.2 billion by 2100; more recent UN projections expect a lower peak of around 10 billion later this century. Either way, many more homes will be needed, often in places where building materials are expensive or hard to transport. A printer that can turn the ground beneath it into a shelter is an attractive idea for such settings.
Most 3D-printed houses elsewhere, for example in the United States and Mexico, are printed from cement-based mortars. They are fast and strong but carry a much higher carbon footprint. TECLA's contribution is to show that a printer can produce a habitable, attractive shell from unfired earth.
Limits and open questions
It is worth keeping the claims in proportion. TECLA is a prototype, not a mass-housing programme, and the printer built the walls, not the whole house. Doors, windows, the roof covering, plumbing, wiring and finishes were still made and installed by people. Printing times also depend heavily on soil type, weather and the size of the building.
Earth buildings need good protection from water, careful mix design and local building approval, and soil varies a lot from place to place. Long-term data on how printed earth walls perform over decades is still limited. Costs quoted for printed houses rarely transfer directly from one country to another, because land, labour, regulations and services make up a large part of the price.
Even so, the project has influenced the field. It showed that two printers can collaborate on one structure, that natural materials can be extruded reliably, and that a printed house can be beautiful rather than merely functional.
Visiting and following the project
TECLA stands in Massa Lombarda, in the province of Ravenna, close to WASP's base, and has been used to showcase the company's technology. WASP and Mario Cucinella Architects publish updates on their own websites, which are the best places to check for current information about visits and new earth-printing projects.
Sources: Image and video: WASP and Mario Cucinella Architects; WASP: TECLA, 3D printed house; SOS – School of Sustainability: TECLA, a prototype 3D printed global habitat; first spotted via Truth Theory.
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