Kanda Coffee, Tokyo

Beneath Kanda Train Station, amidst countless izakaya and bars, the site presented a significant challenge: buildings could traditionally be constructed only as single-story structures. We were commissioned to design a two-story building, optimizing the available space by minimizing the sections of the structural elements.

Within the compartment, divided by concrete walls supporting the Yamanote railway, we developed a two-story structure using steel elements with a maximum section of just 100 mm. These elements were verified for vertical static loads, but under seismic conditions, the structure proved too flexible, risking collisions with the existing perimeter walls.

To address this challenge, braces were added between the columns. These not only delineate seating areas but also increase the overall rigidity of the structure, limiting deformations during earthquakes. This solution prevents hammering effects, ensuring both structural safety and user comfort.

The floor slab, composed of corrugated steel decking cast within the 100 mm structural element, leaves the beam framework exposed. This approach is not only technical but also aesthetic: the building’s exoskeleton becomes a prominent spacial feature, revealing its distinctive geometry. In doing so, the structure gains a unique character while making its structural logic immediately legible, transforming technical solutions into a narrative and visual value.