Building No. 21 (1914-1961) [From tenement houses to the prototype of large-scale office buildings]

Building 21, which stood in the current Shin Tokyo Building block at roughly a quarter of its size, was designed by Yasuoka Katsuya. Building 13 marked the completion of the brick-built office buildings of the First Block London district, and from Building 14 onwards, the buildings continued to follow the tenement-style floor plan, even though the main structure changed to reinforced concrete. Building 21 adopted a large-room floor plan similar to current rental office buildings, with each tenant sharing the entrance hall (floor plan "octagonal hall"), stairs and toilets, and facade also changed from a single window style to a series of large openings reminiscent of horizontally extending windows, in response to the office space that spreads out horizontally. However, the plan clearly states that bricks will be used for the finish, suggesting an intention to harmonize with the streetscape of First Block London and create the entire district. Furthermore, an article in Architectural Magazine No. 331 reporting on the completion of the building stated that "the costs of spot cleaning in the corridors, water fees, floor cleaning and elevators, etc. shall be borne by the lessor." It seems that Building 21 not only provides a model for today's large-scale office buildings, but also a philosophy for building management.