The ephemeral outdoor auditorium by CODA in the FADfest

The exterior auditorium of the FADfest that takes place in Barcelona, that was built by CODA, Computational Design Affairs, is a large shell under which an auditorium with capacity for 570 people is built.

This year the main events of FADfest were staged on a very special “continent”: an outdoor auditorium built especially for the occasion inside the Elisava Gardens Lake of the Disseny Hub Barcelona.

The project was designed by CODA – Computational Design Affairs the team that won the competition to design the outdoor auditorium of the FADfest. The jury, comprised of Pep Quílez, Miguel Angel Aguiló, Samuel López, Lali Sabartés and Ximena Pérez, valued the variety of examples provided, the aesthetic quality of the works and the harmonious combination of computational design and resources that evoke the craft of basketry that is so typical of the country, plus the multidisciplinarity of the team.

The young architects’ practice designed a great 400m² shell under which an auditorium was located, with capacity for 570 people seated and 380 standing.

The creation process

After studying the potential of the different locations around the Disseny Hub Barcelona building, the FAD as the organizing body and CODA as the project’s architects decided to locate the auditorium inside the Elisava Gardens Lake, between Avila and Álava streets, taking advantage of the draining operation that had to be carried out in summer for maintenance and cleaning.

The construction solution adopted was a hanging reticular shell that minimized the effect on the elements in the surroundings through non-invasive foundations. The grid was made from tubular fiberglass profiles connected with rotating joints from a scaffolding system. Above the lattice of tubes, a SIOEN PVC canvas distributed by Ventas Internacionales S.A. was added. The canvas patterned by TP Arquitectura y Construcción Textil, besides guaranteeing its resistance to fire, ensured impermeability in the event of rainfall and good audiovisual quality. The ensemble of cables, tubes and canvas weighed 6 kg / m2 and was suspended from a heavy-duty crane provided by the company Gruas del Vallés.

The final form of the shell results from a form-finding process where it is the material itself that computes the form. In this regard, the challenge was to find the final form that the structure acquired through its own weight, where the only thing that was designed was the length of the cables. In this way, once elastically deformed, it was the system itself that found a state of equilibrium. The project’s virtue was to achieve stiffness from straight and flat industrial elements, which by deforming them in a controlled way could generate efficient double-curved shells.

This design process was possible thanks to the integration of the calculation methods in a parametric modelling environment. The simulation was performed on one hand by comparing two methods of non-linear analysis, with dynamic relaxation (kangaroo2) and with force density (Wintess) and, on the other, calibration—with physical trials.

The FADfest shell is a demonstration that the new paradigms of design plus computation effort can reduce the environmental footprint of constructions. High-tech design, low-tech fabrication.

The FAD would like to thank all the professionals who worked to make this project possible, especially CODA, Barcelona Ciclo del Agua S.A. and Gruas del Vallés, for their effort and rigour, which have turned the physical setting of the FADfest into a unique and pioneering space.