The project is a renovation to divide a 130-year-old storehouse built in the Meiji era into a French restaurant “NIM” and a residence for the owner-chef and his family in Daishinmachi, that retains the traditional townscape of Hida Takayama. The exterior is almost untouchable because the storehouse is located in the Important Preservation District for Groups of Historical Buildings designated by Takayama City. The client asked me to take advantage of this constraint and create an interior with a worldview that would be unimaginable from the exterior.
I have visited the existing storehouse without any preconceived notions or design ideas. The structure was very impressive because it was quite large for a storehouse, with a frontage of 4 spans and a girder of 8 spans and it has a rugged frame typical of Takayama, with a ridgepole made of splendid logs and two intersecting beams. I felt that the scale of the space,the framework of the structure, and the unique atmosphere created by the darkness of the storehouse should be respected. On the other hand, it was difficult to divide into two uses by inserting a wall without destroying this spatial characteristic. The design theme was the action itself of inserting a wall to divide into two uses and the interior of the store was completed with only the inserted wall because I wanted to limit the scope of modifications due to the budget being limited.
First, the space on the second floor was divided into north and south in order to bring in as much light and ventilation as possible to the residential area within the constraints of the limited existing window positions, taking advantage of the space's long east-west direction. It will be difficult to see the seating audience on the upper floor from the kitchen on the lower floor if the upper and lower floors are placed on the same plan. By dividing the space into two parts, east and west, the upper and lower floors are connected in an L-shape.
Each room of the inverted house is connected in an L-shape so that the signs of the family can be conveyed to each other similarly. After that, I thought about the effect of the presence of the wall on the space. The powerful framework is emphasized rather than hidden by arranging the wall inserted on the second floor away from the core of the ridgepole. In addition, the part of the wall is suspended on the lower floor through the atrium and combined with the suspended staircase made of thin iron plates, it creates a feeling of floating. The unique atmosphere of the storehouse is brought out by making it behave like a ghost. The misalignment of the wall reinforces the lacking earthquake-resistant performance while it has the characteristics of the existing structure mixed hardness and flexibility by the effect of not being too effective even though it is an earthquake-resistant element.
This dully reflective wall by attaching a metal plate functions as a “mirror” that completes the space by clarifying the material contrast with the existing part and creating a virtual image of the space that was lost in order to divide the use. Creating a new space by inserting a wall is to breathe new life into the space as a base for living and livelihood while keeping the flow of time from the Meiji era in the space. And it is a “mirror” that reflects the chef's desire to create a world of cuisine that has not yet been seen, while making the most of local ingredients.
Structural design concept
The mud walls of storehouses are thicker than those of houses, and have extremely high shear strength. In addition, the outer walls in the longitudinal direction have sufficient seismic resistance because of the minimal openings. On the other hand, the openings in the transverse direction are large, part of the mud wall had been
removed in this building. As a result, there was a lack of seismic resistance on the first floor. I decided to reinforce the wall with inner high-strength walls to give sufficient resistance at first.
The architect's proposal made structure more improved. That was to insert walls by shifting them from the existing framework. Inserting high-toughness walls into the interior has the advantage of increasing the amount of energy absorption. However, adding walls has a risk of changing the rigidity balance. In general, a storehouse building gradually deforms under its own weight and some earthquakes so that the forces through it stabilize over a long period of time. Therefore, low-rigidity walls could maintain existing forces. The effectiveness of the wall can be weakened by shifting the wall from the framework or making the wall on beams. Low-rigidity and high-toughness characteristics are imparted by steel plate reinforcement and short wall lengths. The wall, which is inserted offset from the existing frame, acts like a damper for the building throughout the frame.
Team:
Architects: Hajime Aoyagi + Ayaka Aoyagi / aoyagidesign
Structural Design: Takuya Asamitsu / Asamitsu Structural Design
Design assistance: Kei Miyamoto
3D Modelar: Tsubasa Sano
Environmental Design: Masamichi Oura
General Contractor: Nagato-Kensetsu
Photographer: Koji Fujii / TOREAL