The students and researchers of the Postgraduate Programme in 3D Printing Architecture (3DPA) have expanded the 3D-Printed Earth Forest Campus by building Teixit, an innovative structure 3D printed from local earth. Utilizing computational design and robotic technology, this unique structure demonstrates that earth walls can be both structural and perforated, offering new opportunities for sustainable architecture. Teixit complete a 100 m² low carbon emissions building prototype, using local soil, natural materials and the pioneering Crane WASP 3D printer. Adjacent to TOVA, 3DPA’s previous prototype constructed in 2022, Teixit extends the living and working area of the forest robotic campus in the Collserola Natural Park.
Photo © Iwan Baan
In recent years, the construction sector has been faced with many challenges, one of which being the embedding of a fully circular building process, a complex adaptation for a system involving multiple disciplines, stakeholders and materials in its value chain. Out of several solutions, 3D printing with earth, consisting of a layered deposition of raw material sourced on-site, has been rendered as one of the most sustainable methods for a circular economy in the construction industry using additive manufacturing techniques and biomaterials. 3DPA is a programme of applied research with the aim to apply state of the art technology to today’s construction paradigm. It is axed around the continuity of the development of a body of research long explored at IAAC together with our industry partner WASP. This year, the programme counted 20 students from all over the world.
3DPA uses cutting edge technology of 3d printing with earth, an ancestral material, locally sourced and non contaminant. Reinforced by natural fibres, the unfired earth walls with its natural stone foundations and timber roof, lead to a carbon neutral building solution with a strong emphasis on controlled penetration of daylight and the potential of natural ventilation.
Teixit builds on 8 years of development of knowledge by addressing the complex question of lightness: how much daylight can travel through a structural earth wall?
The relatively low mechanical strength of earth means that its use in traditional construction often leads to walls that are both thick and opaque. Windows are normally constructed with the introduction of a different constructive element which can make building processes more complicated and less fluid. As a result, earth walls tend to be blind and earth architecture relatively dark. One of the strengths of 3d printing, its digital workflow and the consequent flexibility in design, is that we can design a wall by customising its geometries. Combined with a careful understanding of the robotic tool, the material behaviour and its structural properties, one can envision the construction of a wall that contains porosities, and therefore let in a controlled amount of light through its depth, across the space.
Construction © 3DPA
Teixit is a 50m2 open space consisting of 3 standing earth printed walls that support and anchor a large wooden roof. The walls rest on a gabion -a natural stone foundations-, on which a recyclable earth formwork served to cast a water resistant earth mix. From there the 12 linear metres of earth (6 tons) walls were printed in a period of 4 weeks. Once the walls were dry enough, post tensioning cables were inserted through their inner cavities to anchor the roof structure to the foundations to balance the wind uplift forces.
Unfired earth walls are vulnerable to water. Teixit’s walls are protected by three mechanisms: an overhanging roof that reduces strong contact to rain, a water barrier avoiding water coming from the ground by capillarity, an integrated anti erosion geometry and a final organic oil water repellent treatment.
3D printing, a novel digital technology, enables new design possibilities that can challenge over-standardisation in construction. It can lead to an architecture that adapts not only to its climatic context but also to the availability of local resources and to the needs of the specific user or community. With earth as primary construction natural, this architecture can reconcile with its environment to produce circular, affordable and low emission dwellings.
This year’s research was reinforced by a recent collaboration with Hassell Studio for the design of a community center in Hope village in Tanzania, with the charity foundation One Heart. The project aimed at integrating printed earth walls in a humid and hot climate, where earth walls are traditionally thin and contain large openings to maximum natural ventilation.
Photo © Iwan Baan
Project credits
Directors
Edouard Cabay
Alexandre Dubor
Coordinator
Yara Tayoun
Faculty
Oriol Carrasco, Senior Fabrication Expert
Elisabetta Carnevale, Material Expert
Alicia Huguet, Structural Expert – SOCOTEC Spain
Faculty Assistants
Secil Afsar, Fabrication Assistant, Material Research Expert
Nestor Beguin, Computational Expert
Collaborators
Colette, philanthropic organisation
3D WASP, Large Scale 3D printing
SOCOTEC, Structural Consultant
Hassell Studio, Architecture Consultant
Vervictech, Enzymes provider
Researchers
Jose Antonio Gutierrez Rangel, Joseph Milad Wadie Naguib, Justin Hanlon, M´Hamed Alila, Maria Kaltsa, Mark Francis, Noel Akroma, Sakshi Pawar, Sara Ayoub, Vesela Tabakova, Yang Xiao
Special thanks
Areti Markopoulou, Mathilde Marengo, Daniel Ibanez, Ricardo Mayor, Shyam Zonca, Sheikh Riaz, Philip Wienkamper, Pilar Xiquez, Daniela Figueroa Claros, Jorge Ramirez, Massimo Visiona, Massimo Moretti, Francesca Moretti, Laia Pifarre, Bruno Ganem, Xavier de Kestelier