Full Circle

When Osaka held its first World Expo in 1970, an awareness of the planet’s finite resources was only just beginning to permeate the global agenda; ‘Earth Day’ was founded the same year declaring the environment political. The Expo’s master plan unfolded, largely oblivious to these novel demands, to a design led by Metabolist architect Kenzo Tange, dominated by concrete, steel, and geodesic domes; and while pre-fabrication and modularity were explored, most of the pavilions were demolished afterwards.

Fifty-five years later, Osaka welcomes its second World Expo for 2025, and climate awareness has progressed to climate crisis; the Anthropocene has imposed a geological force so great that it now threatens to exceed planetary boundaries and irreversibly alter the natural environment, the biosphere. In this context, concrete, high in embodied carbon and impossible to recycle, among other culprits, is at the center of debates surrounding the impact of the built environment on climate change today, which overall accounts for approximately 60% of global resource consumption, 35% of energy consumption, as well as 50% of emissions and 50% of global waste generation.

With the purpose of an Expo providing an international stage for experimental thinking and innovative solutions, LAVA elected to tackle the impact of the built environment on the planet through the German Pavilion aligned with the United Nations’ Sustainable Development Goals: “To construct a sustainable and future-proof post-anthropocene society where nature, technology and humanity mutually cooperate, we need to fundamentally rethink the way we design, produce, operate and, above all, reuse and adapt our architecture and urban design. A cradle-to-cradle approach results in a closed loop, zero-waste circular system in which all consumables are fed back into the cycle, radically minimizing the consumption of resources,” explains Christian Tschersich, Associate Partner at LAVA.

Under the theme of ‘Designing Future Society for Our Lives,’ the architects have activated a circular pavilion titled ‘Wa! Germany.’ ‘Wa’ means "circle" or "harmony" in Japanese. It invites the public to follow an accessible spiraling pathway through a series of cylindrical structures while collectively contemplating the possibilities of a circular economy—questioning societal implications, the life cycles of materials, and the role of digital technology. As an industrial force, Germany is poised to contribute to this shift from energy harvesting to material science, as Tschersich describes: “Architecture is a vital interface between the biosphere and technosphere; both the framework and interface for resource distribution and societal interaction, fluidly combining aesthetics, functionality, and sustainability.”

LAVA predicts that in the future, in addition to constructing buildings entirely from natural products, the functions of the biosphere will be embedded into urban environments as blue-green infrastructure. The outdoor design of the pavilion is therefore equally important where an open-air event space is surrounded by planting that purifies water and produces food. The garden temporarily hosts 21 trees, bamboo, and rhododendrons on loan from an Osaka nursery. Green roofs and shady, climate-resilient reeds and grasses cool the air flowing through the pavilion.

The flow of water is also strategically integrated as a learning experience for visitors; with flash flooding and extreme heat events increasing globally, water security is a crucial challenge for urbanists of this century. Historical daily precipitation data, considering both average rainfall as well as typhoons, informed permeable paving, gravel trenches, and open gutters that connect to a rainwater storage tank and bioswales that maintain soil humidity. Together, these steps prevent stress on the Expo rainwater pipe, reducing the possibility of flooding.