The Prada flagship store in Tokyo combines an overall figural shape with inset stacked floors and nested tubes to create a steel and glass shopping icon. A structural exoskeleton made from 7-1/16–by–8-1/16-in (18 by 20.5 cm) steel I-sections welded on site and encased in a fire-resistant layer of calcium silicate form a grid of rhomboids, each 10 ft 6 in by 6 ft 6 in (3.2 by 2 m).

The entire building is set into a concrete tub, where isolation mats stabilize the structure during earthquakes. Inside, seven regularly spaced concrete floor slabs span from the exterior skin and interior circulation cores and conceal mechanical and electrical distribution.

Three horizontal tubes, aligned with groups of four rhomboids on the facade, are nested in the floor plates. These tubes enclose areas for changing and checkout and provide lateral stability. Extruded from the diagrid facade, yet embedded within the figural building volume and bifurcating floors, these nested spaces complicate distinctions between exterior and interior or from floor to floor, producing an intricate fusion of skin, structure, space, and form.

Book Reference: 

Manual of Section
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