It is a complex of church school (2nd floor) and nursery (1st floor) administered by Protestant Christ church. The premises are located at a greenery area in Yokohama city surrounded by fields, parks and hills in the neighborhood. It has been planned in the open space such that places for children to stay are mixed into forest with rich natural environment.
Drawn continued line in the forest in a spiral manner mixes buildings with the forest and indoor part with outdoor part as if they were stirred by hands, simultaneously creating individual classrooms and open spaces as well. The continued line runs through the forest while avoiding and surrounding trees. It is a building with new mixture of indoor and outdoor parts.
We’ve selected wooden construction as a place for children from infant to senior in high school to stay. Making wooden building of wood framework, wood floor and wood sash to be clear and light, we’ve realized a transparent wooden construction. In a simple grid building, steel frames are adopted to five courtyards to bear earthquake load. Since pillars of solid steel of 110 square are fit between wooden pillar and sash, their existence is successfully eliminated without any sense of discomfort while they are exposed without being hidden.
Glass sliding door is equipped at the interface between indoor and outdoor area. Light falls and spreads into the building through the trees and winds from the forest run through the building. It is possible for children to vividly spend their time both at indoor space where they feel as if they were in the forest and at outdoor area where they also feel as if they belong to the building. School children go to each class room after holding morning service in the hall at second floor. They take classes in sunlight falling through the trees and read books in the forest. Children in nursery freely run around from indoor to outdoor while taking a nap with comfort brought by forest wind.
The building has been built by trying to figure out a new concept for building establishments in forests. I hope not a building excessively managed artificially but such easygoing building defined to lie between natural and artificial will be a good place for children to stay.
Feeling of area not too ruled
Each class of the nursery school on the first floor and the church school on the second floor consists of two or three kids. Two to three classes make one nursery room or classroom. Each small classroom is open in terms of space, vision, and distance, allowing the children to interact with each other, going beyond the boundary of classes. The teachers can watch the kids over a wide area, including the outdoor, so that the kids can spend their time freely at various places indoors as well as outdoors.
Each classroom and sound
The floor planning consists of classrooms and a hall. Between classrooms and between a classroom and the hall are transparent acryl sliding doors. When the door is closed, the vision is transparently connected but the classroom can be used as a closed space. The acryl door is sound-proof and effectively shuts off sounds. Being small the building, the floor planning is made, so that good relation of sounds can be created, by, for example, separating the classrooms of the lower grades of the primary school from the classrooms of junior high school students as much as possible.
Transplant wooden building
A new wooden glass building was proposed by using the cross-sectional scale of a general wooden building we are used to and without using braces and plywood wall. A steel frame that becomes an earthquake-resistant façade of a court glass box blends in the wooden frame placed in grid. Taking into consideration ensuring safety for children and being used as a shelter in case of a disaster, a glass earthquake-resistant wall that can maintain the texture of wood and transparency of glass was developed. By combining glass materials, which are hard and easy to break, with an oil dumper specially tuned, a preserving glass structure that can control and absorb the force of an earthquake applied to the glass was made up. The strength of the toughened glass used for the glass earthquake-resistant wall was confirmed and the safety was proved through a full-scale experiment.
About air conditioning (air-operated floor heating and cooling system)
Because the entire surface of the outer wall is glass, an air-operated floor heating and cooling system was employed, considering influences on human bodies of the coldness radiated from the window glass in winter. This system sends warm air blown out from an air-cooled heat pump to the air layer of double floor. The air passes through under the floor, conducting heat, and is blown out of the floor outlet by the window. This air flow slightly warms the floor surface while the warm air blown out of the outlet by the window
shuts off cold radiation from the window glass.
In summer, wind is basically allowed to flow through naturally. When it rains and the windows cannot be opened, it is planned that the air is cooled (auxiliary cooling) by the heat pump performing a cooling operation.
The air-conditioning system is designed to slightly reduce the heat and coldness without too much controlling them artificially.
ARCHITECT TAKESHI HOSAKA
STRUCTURAL ENGINEERS HITOSHI YONAMINE / OVE ARUP & PARTNERS JAPAN Ltd
PHOTOGRAPHER MASAO NISHIKAWA
CLIENT HIROSHI IKEDA / HONGODAI CHRIST CHUCH
QUESTIONARY TO PRODUCT INQUIRY
Name of the project Hongodai Christ Church school & nursery
Location of the project Yokohama, , JAPAN
It is far from Tokyo about 40min. by the train .
structure wooden-structure + steel
Site 1332.92 m2
Building area 265.97 m2
Total Floor area 531.94 m2
Building height 6410 mm
No. of floors 2F
Building function private church school & nursery
(Name) Takeshi Hosaka
TAKESHI HOSAKA ARCHITECTS
Design September 2008 – May 2009
Planning start (M/Y) February 2008
Beginning of construction June 2009
Completion February 2010