The IAAC’s Postgraduate in 3D Printing Architecture (3DPA) recently concluded its 7th edition, which focused on sustainable architecture through additive manufacturing of earth structures. The programme, which culminated in the construction of the prototype VOLTA, explored this year the concept of the “Fifth Facade”.

Following the construction of TOVA, the IAAC’s first 3D Printed building using earth and a WASP Crane, which successfully certified the potentials of 3D printing with sustainable materials in response to the current climate challenges and housing emergencies, 3DPA further explored novel construction techniques enabling a 3d printed structure to span between walls and achieve slabs and a roof, or “the Fifth Facade”.


“The Fifth Facade” Project of 3DPA 22-23, IAAC, ValldauraLabs © Nestor Beguin

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.

This showcases the development of student work through an intensive research competition phase, resulting in the emergence of exciting construction techniques that are both structurally and spatially viable. A design-to-production process led to the creation of a 1:1 printed prototype of a vaulted structure, serving as a first demonstrator for the potential emergence of building proposals. It offers a vision of what a student housing facility, constructed using earth 3D printing, would look like in the urban context of the metropolitan area of Barcelona.

Living Prototypes: A research-industry collaboration on the future of biomaterial living spaces

The potential of a more holistic approach to the use of biomaterials in the built environment, with the assistance of advanced technologies, has been tested by IAAC, other research institutions and their respective industry partners, through Living Prototypes, a collaborative project funded by the research innovation programme, Zukunft Bau and curated by the ANCB in Berlin. IAAC in Barcelona working with earth, alongside its industry partner WASP from Massa Lombarda, collaborated with CITA from the Royal Danish Academy in Copenhagen (Bioplastics) and ITKE from the University of Stuttgart (Flax Fibre) respectively with industry partners COBOD from Copenhagen and FibR from Kernen.

As the outcome of these collaborations and parallel research renders possible a bio-based future for building components, IAAC 3DPA’s programme is now equipped to tackle the fabrication of larger buildings in accordance with the global construction market’s requirements for the coming decades.

Left: Living Prototypes exhibition details © Hendrik Benz. Right: Results from a collaborative workshop between ITKE University of Stuttgart, Institute of Building Structures and Structural Design and IAAC Institute of Advanced Architecture of Catalonia, 3DPA 2022-23.

The achievement of this year’s 3D printed earthen structure was the result of research groups on the topics of fibre reinforcement and optimised placing, structural geometry, lost scaffoldings and active-bending support systems. The design process was initiated with a first competition phase on the design of a small earth 3d printed structure that can fit one person, spans over a roof, and fits within one crane printing radius (4m). This phase led to six different structural solution proposals developed in an intense competition phase that would allow for the final development of a unique 1:1 3d printed prototype in the Valldaura Labs facilities of the IAAC, on the outskirts of Barcelona. The image represents one of the 6 design proposals, a Fibre supported cantilevers printing strategy for the fifth facade.

Render: Fibre supported cantilevers is a project of IAAC, developed in the 3DPA – 2022-2023 by the student(s) Teodora Moraru, Nestor Beguin and Ionut Adrian Patrascu during the course 3DPA 22/23 : Competition with Edouard Cabay, Alex Dubor, Oriol Carrasco and Michelle Bezik.

Construction: 1:1 Prototype Demonstrator

One of the main goals of 3DPA is to foster the creation of a stable and sustainable construction system through km-0 robotic additive manufacturing. For this purpose and for the second year in a row, the location chosen for the prototype construction was Valldaura Labs, the IAAC´s self-sufficient habitat research centre, located in the Collserola Natural Park. As for TOVA, the printing material is extracted and processed on site, an approach allowing to “close the loop” on the circularity in the construction process. For this prototype, 5.4 tons of material were used in 3D printing the prototype over a span of 15 days.

“The Fifth Facade” Project of 3DPA 22-23, IAAC, ValldauraLabs © Shazwan Mazlan

The prototype design is composed of 3 walls that form 2 arched vaults. One vault is a walkthrough, and the other vault is smaller and does not behave as a walkthrough, rather a space for utility. The structural axes of the vault walls determine the direction and angle of the adaptive support system positions.
The foundation of the project is made out of a layer of gabion cages loaded on site following the excavation of the prototype outline. The sub-foundation on which are deposited the first layers of the print was made out of geopolymer casted within printed layers of the outline geometry, for a total volume of 0.99 m3 at a height of 0.30 metres.

As previously stated, the aim of 3DPA 22-23 was to achieve the fifth facade, a challenging topic that required various active geometrical strategies and passive strategies such as active bending scaffolding and, later on, post-tensioned fibres placed in cross-sections of the print. The geometry chosen was a compilation that resulted after the completion of the competition phase. The pavilion was designed as a double vaulted geometry, composed of multiple descending arches, aiming to enclose the “roof” of a space. The demonstration of the possible 3d printing of a “Fifth Facade” was attained through the successful spanning of 3d printed layers to achieve a timber-supported arched structure. The timber scaffolding system, an active-bending support system, had a screw system to modify the length of the elements, allowing it to adapt to the shrinkage of the earth construction as it gradually dries following the printing process. Hence, the timber scaffolding system is designed for disassembly and can be removed and reused for building other components, after the completion of the drying period of the prototype.

Active-Bending structural system, 3DPA 22-23, IAAC, ValldauraLabs

Architectural Vision: 3D printed earthen building solutions for student housing in Barcelona
This year’s Research’s focus on the Fifth Facade has led to the emergence of exciting construction techniques that enable to span between walls and achieve floor slabs and roofs. The prototype further demonstrated the possibility of achieving “the Fifth Facade” in 3D printing earth architecture (3DPE). The latest conclusions from the Competition phase helped to develop these techniques into systems that are both structural and spatial. The Vision, through the design of a building proposal, focused on the relationship between structural and spatial organisations.

IAAC’s 3D Printed Student Housing is a project of IAAC developed in the3DPA – 2022-2023 by the student(s) Tinsae Tsegahun Mengistu, Marina Nassif, Milad Mehdizadeh and Huanyu li during the course 3DPA 22/23 : Vision with Edouard Cabay, Michelle Bezik, Alex Dubor and Oriol Carrasco

The project proposals explored the various ways to utilise the flexibility that 3D printing offers in order to achieve non-standard architectural solutions adapting to programme needs in student housing in an urban environment: spatial quality, community-based and adaptable spatial organisation, building expansion strategies, structural design, connections, and the approach to 3DP construction in urban settings.

Trinitat Mosalas is a project of IAAC, developed in 3DPA – 2022-2023 by the student(s) Dnyaneshwari Mete, Paco Pioline, Kevin Mwangi Njoroge and during the course 3DPA 22/23 : Vision with Edouard Cabay, Michelle Bezik, Alex Dubor and Oriol Carrasco


In summary, the postgraduate programme in 3D printing architecture has provided the researchers with an opportunity to explore and push the limits of conventional architecture design techniques. A final prototype of the fifth facade of an architecture was developed using 3D printed earth, showcasing the ability of this technology to respond to structural challenges, further pushing the potential implementation of this construction process in the urban built environment. This approach represents a creative and critical thinking about the future of architecture in the current climate context, and highlights the importance of interdisciplinary collaboration and the integration of new technologies in the field. The successful completion of this year’s prototype demonstrates the endless possibilities for innovation and design as we continue to embrace the potential of 3D printing in architecture with biomaterials.

Project credits

Edouard Cabay, Alexandre Dubor

Yara Tayoun

Oriol Carrasco (Fabrication Expert), Elisabetta Carnevale (Material Expert), Ashkan Foroughi (Computational Expert), Guillem Baraut (Structural Expert), Tzu-Ying Chen (Robotic Fibres Expert)

Faculty Assistants
Secil Afsar (Fabrication Assistant), Aslinur Taskin (Fabrication Support), Michelle Bezik (Design Support), Andre Aymonod (Student Assistant), Ioannis Moutevelis (Student Assistant)

Abanoub Nagy Abdou Mikhail, Adrian Ionu? P?tra?cu, Ali Salamatian, Dnyaneshwari Mete, Francisco Magnone Rienzi, Huanyu Li, Jett Demol, Javad Norouzi, Kevin Mwangi Njoroge, Kingsley Claudin, Mara Luisa Müller-de Ahna, Marina Nassif, Marta Navarro López, Milad Mehdizadeh, Shazwan Mazlan, Nader Akoum, Nestor Beguin, Paco Pioline Sanchez, Teodora Moraru, Tinsae Tsegahun Mengistu

Colette, philanthropic organisation
3DWASP, Large Scale 3D printing
SOCOTEC, Structural Consultant
ITKE, Stuttgart University
Zukunft Bau, Research Innovation
Aedes Architecture Forum

Special thanks
Areti Markopoulou, Mathilde Marengo, Daniel Ibanez, Ricardo Mayor, Shyam Zonca, Sheikh Riaz, Philip Wienkamper, Pilar Xiquez, Daniela Figueroa Claros, Jorge Ramirez, Jordi Guizán Bedoya, Massimo Visiona, Massimo Moretti, Francesca Moretti, Laia Pifarre, Bruno Ganem, Hendrik Benz, Martin Tamke, Aine Ryan, Dunya Bouchi.