Mitsubishi Ichigokan Annex Warehouse (East Building No. 9, West Annex)
[The ultimate pre-war Renovation]

This time, we're looking at the warehouse attached to Building No. 1, which was quietly built in 1906 (Meiji 39) behind the former Mitsubishi Ichigokan (completed in 1894 (Meiji 27)) (facing Naka-Naka-dori Street). At the time, there was no central station (Tokyo Station) and commuters relied on streetcars or rickshaws, so the building was actually used as a rickshaw parking area (first floor) and a rickshaw driver's rest area (second floor). The two-story brick building has a floor area of 585m², a tiled roof, and a vertically divided tenement-style floor plan, with stairs laid out between each section. The blueprints bear the seal of Yasuoka Katsuya. This building underwent two major extensions and renovations over the course of approximately 60 years, until it was demolished in 1967 (Showa 42), and was eventually used as an office.

The first Renovation was in 1913 (Taisho 2), when an additional floor was added, making it three stories tall (expanding to 992m2). The extension method involved a reinforced concrete structure being placed discreetly on top of the brickwork. Details of the joints between the brickwork and the reinforced concrete remain as diagrams of the steel floor beam layout. Recently, there have been examples of SRC structures being added to the third floor of the Marunouchi Station building at Tokyo Station, but this was over 100 years ago. The ideas and technical capabilities of the engineers at the time are astonishing.

The second Renovation was around 1936 (Showa 11), when the building was converted into offices. The floor plan, which had been a vertically divided row house, was changed to accommodate entire floor rentals or entire building rentals by adding a new shared staircase to the center and openings in the brick partition walls between tenants. Furthermore, while there had previously been no entrances or exits on the first floor facing Nakanaka-dori Street, renovations were carried out to create large openings, and an office entrance and car garage were installed. Furthermore, the previously featureless brick facade that resembled a warehouse was given new treatment, with the window frames, tiling of the lower part, and entrance fixtures, transforming the building into a secession-style office building.

The Mitsubishi Ichigokan Warehouse has survived for over 60 years by adapting its use and facade to suit the changing times, and it is no exaggeration to say that it is the ultimate example of pre-war Renovation architecture. We hope to inherit the wisdom and spirit of our predecessors and continue to develop it further.