The immersive exhibition "Boltshauser Architects – Radical Materiality" at the Architecture Salon traces clay's transformative journey through their work: from raw material processing through artistic research and innovation to realized buildings. Today, the practice is pioneering clay's potential as a hybrid building material, expanding its applicability through strategic combinations with complementary materials while advancing its scalability for contemporary design. At Roger Boltshauser's laboratory at ETH Zurich, hands-on experience from built projects is rigorously studied and validated, with research findings feeding directly back into prototype development. This virtuous cycle—where teaching, experimentation, scientific analysis, and knowledge-sharing reinforce one another—is essential to establishing clay as a modern building material. One that delivers not only environmental benefits, but also meets today's rigorous standards for safety, performance, and longevity.

Testing materials repeatedly—in the lab, through mock-ups, in the workshop, during the casting of elements, and on-site—is central to Boltshauser Architects' methodology. This intricate interplay between knowledge gained through practice, the pursuit of a distinctive architectural language, and design questions that feed back into scientific inquiry defines their work. The dynamic balance between research and building practice is embedded in the contemporary-archaic, instantly recognizable character of their structures. At the core lies a single question: How does all of this culminate in architecture built to last? For Boltshauser Architects, durability is sustainability's most vital dimension—and beauty, atmosphere, sensory richness, and the genuine regard of the people who inhabit these spaces are what guarantee it.

Two clay walls—constructed both as exhibition pieces and as functioning test walls for an active building project—partition the space into three distinct zones that walk visitors through the material's diverse applications in a processual, immersive way. This is no conventional architecture exhibition, but rather a rich tapestry exploring multiple dimensions of working with clay. The first room presents clay preparation as a spatial installation, where the raw material's texture, characteristic grain distribution, and precise compositional requirements become tangible and visceral. Sourced from the Hamburg region, the clay echoes its historical presence in the Speicherstadt's iconic clinker brickwork across the way, while its unfired, CO₂-neutral form offers a direct contemporary alternative. The exhibition's centerpiece is a table of curiosities—a carefully composed ensemble of tools, model studies, research sketches, compression cubes, and stress-test samples revealing the many incremental steps toward contemporary clay construction. What follows are models of competition entries and completed buildings, each captivating in its own right through sheer craftsmanship. Detailed portfolios showcase the office's full range of work, from pure clay structures to hybrid high-rises.

These are complemented by sketches, photographs, and original prints by various artists. Roger Boltshauser's own drawings—both experimental and architectural—engage with existing forms, and establish a dialogue with Arnulf Rainer's reworked plant studies and Heidi Bucher's latex wall casts. Sandro Livio Straube's photographs document the building process as art, while Philip Heckhausen's images of traditional clay construction in France, Spain, and Morocco deepen the research narrative. Six original vintage prints from Daniel Schwartz's landmark photographic series on China's Great Walls reference erosion and impermanence, completing the material's cycle.

Opening reception: 13 November 2025, 7 p.m. Welcoming remarks by Franz-Josef Höing, Chief Planning Director of Hamburg, followed by a guided tour conducted by Roger Boltshauser.

Closing event: 15 January 2026, 7 p.m. Features a lecture by Roger Boltshauser and guest speakers.

www.architektursalon.de