立地
敷地は近頃の世田谷には珍しく緑の多く残る一角にある．老朽化した木造平屋建ての旧宅を取り壊し，
隣接する日本家屋を母屋としてその北側に増築を行うというプログラムであった．増築の予定地は
鬱蒼とした雑木林で，思い切った伐採が必要だったが，大きく育ったクルミ，マツ，カエデの3本は
残すことなった．配置計画はこれらの樹木と母屋，西側のアパートを含めた全体の環境に配慮し，
光，風，景観，プライバシーとヴォリュームバランス，さらに将来的な環境変化の可能性を
検討しながら進められた．
与件
今回の増築部分の住まい手は親子2人の家族である．質実でローコストな建設が条件となった．要求の内容は
「表面的な合理性が生活を規定するような住宅ではなく，生活をつくり上げていくことができる箱」であり，
そのイメージの媒体として建主が提示したものは，曲のカセットと詩や評論のコピー，イメージ・ポスター
であった．ナチュラルでニュートラルな感じのものと，メタリックで近未来的な感じのものが相半ばしていた．
構成
面積的に小規模なこの住宅に豊かな質を付与する下地として，空間単位が相互に連携して全体のポテンシャルを
高めるプランニングを追求した．3室ある居室は，互いに緩やかに連続するようスキップしながら隣接しており，
螺旋状の動線でつながれている．眺望のよい2階は居間とし，平屋部分の屋上であるデッキに開かれている．
デッキは居間の延長であると共に，周辺環境へとつながる接点である．1階より半層スキップしたピロティ上の
個室は，天井を高く取ってそのまま居間に連続させた．ここは個室と居間の要素が交錯した場所として，
この住宅を特徴づける空間である．居間の下部の個室は就寝が主となるため，正方形の中庭と一体の静謐な
空間とした．中庭の上部はカエデの梢に半ば覆われ，デッキの空間と結びついている．各室の特性を生かすため
，外部との接点となる開口部の扱いには特に留意した．中でもピロティ上部の個室の開口は地窓とトップライト
による特殊な構成とし，建主から提示されたさまざまなイメージを反映することを目指した．
構造
基本的には木造在来工法であるが，天井面の意匠的な配慮から，屋根，床はツーバイフォ一部材と構造用合板を現しで
用いて固めている．壁は主に開口部の設けられている南北面を筋違で，閉ざされた東西面を構造用合板で構成した．
材料
周囲の緑地を対比的に強調するため，外装には建主の意向でもある金属系，セメント系の工業製品を使用した．
内装はほとんど木質系の材料を使用し，外装ともうひとつの対比をつくり出している．
Location
The site is located in a corner of Setagaya where there is still a lot of greenery, which is rare these days. The plan was to demolish the old, dilapidated wooden one-story house and build an extension to the north of the adjacent Japanese house, which would become the main house. The proposed site for the extension was a dense forest, which required drastic cutting, but three large trees - a walnut, a pine, and a maple - were left intact. The layout plan was developed with consideration given to the overall environment, including these trees, the main house, and the apartment to the west, and included consideration of light, wind, scenery, privacy and volume balance, as well as the possibility of future environmental changes.
Given conditions
The residents of the extension were a parent and child family. The condition was that the construction be simple and low-cost. The request was
"Not a house where superficial rationality defines life, but a box in which you can build your life", and the media the client presented to convey this image were music cassettes, copies of poems and critiques, and image posters. There was a mix of natural and neutral designs and metallic and futuristic designs.
Composition
As a foundation for giving this small house a rich quality, we pursued a plan in which the spatial units work together to enhance the overall potential. The three rooms are adjacent to each other, skipping between them to create a gentle continuity, and are connected by a spiral flow of traffic. The second floor, which has a good view, is the living room, and is open to the deck on the roof of the single-story part.
The deck is an extension of the living room and also a point of contact with the surrounding environment. The private rooms above the pilotis, which are half a floor apart from the first floor, have high ceilings and are connected directly to the living room. This is a space that characterizes this house as it is a place where the elements of the private rooms and the living room intersect. The private rooms below the living room are mainly used for sleeping, so they are a tranquil space that is integrated with the square courtyard. The upper part of the courtyard is half covered by maple tree tops and connects to the deck space. In order to make the most of the characteristics of each room, special attention was paid to the treatment of the openings that connect to the outside. In particular, the openings of the private rooms above the pilotis have a special configuration with ground windows and skylights, aiming to reflect the various images presented by the client.
Structure
The construction is basically traditional wooden construction, but due to design considerations for the ceiling surface, the roof and floor are solidified using exposed two-by-four members and structural plywood. The walls are constructed with diagonals on the north and south sides, where the openings are located, and structural plywood on the closed east and west sides.
Materials
In order to emphasize the contrast with the surrounding green space, metal and cement-based industrial products were used for the exterior, which was in line with the client's wishes.
The interior is mostly made of wood-based materials, creating another contrast with the exterior.
(Sep 1997 h.taki,a.takeuchi)