key operation inc.: yotsuya tenera
key operation inc.: yotsuya tenera key operation inc.: yotsuya tenera
may 29, 2011

key operation inc.: yotsuya tenera

‘yotsuya tenera’ by key operations inc., tokyo, japan image © toshihiro sobajima

japanese studio key operations inc. has created ‘yotsuya tenera’ a multi-unit apartment building in tokyo. immersed in a residential neighborhood surrounded by shrines, temples and dense housing developments, the building looks to create a protected but penetrable environment that encourages interaction between the homeowners, their space and their surroundings.

set back on the site, the l-shaped building forms a communal courtyard that visually blends the stark and dominant volume with the natural and built environment that encompasses it. a soft and wood-textured concrete looks to create a harmonious appearance that diffuses the buildings mass and relates to the context of the encircling neighborhood.

entrance image © toshihiro sobajima

twelve units are structured around two internal staircases, which extend through the building and terminate at the shared rooftop terrace. a network of internal terraces and balconies merge the boundaries between private and public space, acting as  transitional areas that connects the stairway with the private dwellings. exposed and accessible in their design, the integrated spaces – separated by a series of thin galvanized metal bars – intend to create a stronger sense of community and interaction among dwellers. open to the exterior environment, the core circulation space introduces natural light and ventilation into the depths of the building and each of the homes. 

staircase image © toshihiro sobajima

every unit has been formed to surround the central voids, its shape and layout governed by the staircase and

its position within the larger building. natural, organic and bright, the interior units – available as a studio,

one bedroom or two bedroom flats –  contrast the cold industrial aesthetic of the shared spaces.

staircase with skylight image © toshihiro sobajima

skylight image © toshihiro sobajima

entry to units images © toshihiro sobajima

terrace and staircase image © KOP

(left) terrace (right) entrance image © toshihiro sobajima

corridor in private unit image © toshihiro sobajima

kitchen and dining room image © toshihiro sobajima

exterior image © toshihiro sobajima

courtyard image © toshihiro sobajima

floor plan / level 0 image courtesy of key operations inc.

floor plan / level 1 image courtesy of key operations inc.

floor plan / level 2 image courtesy of key operations inc.

north elevation image courtesy of key operations inc.

south elevation image courtesy of key operations inc.

west elevation image courtesy of key operations inc.

east elevation image courtesy of key operations inc.

section image courtesy of key operations inc.

section image courtesy of key operations inc.

diagram of staircases and internal terraces image courtesy of key operations inc.

diagram of layout image courtesy of key operations inc.

  • The staircases in all the Japanese houses on this site: does no one in Japan suffer vertigo?

    Peter Drew says:
  • I’v seen prisons more inviting…

    Free Form Constructural Realism says:
  • Japanese stairs has always been steep, both in modern and traditional houses, due to a matter of site area, but also because treads and raises are about the same measure (because of the traditional meaning of the square in japanese culture etc.).
    Despite this, i agree with “I’v seen prisons more inviting…”: why this house has to look so rough? Why not to refine the interiors? This bothers me quite a lot. It’s a pity.

    ivan says:
  • I love the clean rough look- it is a completely new way to look at a rough finish.

    Bex says:
  • great place for the condensing unit! the architects forgot about it or they located it there because it makes the space more habitable?

    Norov says:

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