House of Earth | あざみ野の土

The sectional configuration of this house reflects the natural topography of the site, resulting in a three-dimensional skip-floor arrangement. Although it is officially a two-story building, structurally it functions as a three-level system. To ensure efficient transmission of seismic forces across all levels, each floor is connected to the others via orthogonally arranged shear walls.
A distinguishing feature of the architectural design is the extensive use of earthen blocks for interior finishes. As a result, the overall weight of the structure is approximately 20% greater than that of a typical wooden house. However, since sufficient bearing wall has been secured along the perimeter, this additional weight does not pose a structural issue.
The main concern regarding the use of earthen blocks lies in the risk of out-of-plane failure during earthquakes. However, experiments confirmed that the blocks remain in place even under horizontal forces several tens of times greater than their own weight.

Architectural Design: Eureka + Midori Yamada + Wataru Nakamura
Structural Design: Eureka
Program: House
Year of completion: 2021

Photo courtesy of Kurome Photo Studio

本建築物の断面構成は，敷地の高低差によって生じる立体的なスキップフロア状の構成となっており，２階建てではあるが，構造的には実質３層の構成である。そこで，各フロアに生じる地震力を効率的に伝達できるよう，上下の床を必ず直交する耐力壁で連結するようにしている。
また，意匠上の特徴である土ブロックが屋内仕上げに多く使用されるため，本建築物の重量は一般的な木造住宅と比べおよそ２割増しとなっているが，外周に十分に壁量を確保できるので大きな問題とはならなかった。土ブロック仕上げの懸念はむしろ地震時における面外方向の脱落だが，実験により自重の数十倍の水平力に対しても脱落しないことを確認した。

意匠設計：Eureka＋山田宮土理＋中村航
構造設計：Eureka
用途：住宅
竣工年：2021年

写真：黒目写真館