YEARBOOK　2014

10/40

Special Feature010Year Book 2014時間の継承GINZA KABUKIZA（歌舞伎座・歌舞伎座タワー）は、この場所で120年以上にわたって、伝統芸能「歌舞伎」の殿堂として親しまれてきた歌舞伎座を建替えるプロジェクトです。劇場の歌舞伎座だけでなく地上29階建ての歌舞伎座タワーを背後に併設し、地下鉄東銀座駅と直結した地下広場（「木挽町広場」）を整備するなど、銀座の都市再生に貢献した新たな文化の創造・発信拠点を構築しました。今回、劇場の計画においては、外観は第四期歌舞伎座の意匠の継承を、内部においても従来の舞台・客席構成・ロビー空間を踏襲しつつ、観劇環境の改善、バリアフリー性能の確保、トイレのサービス向上、舞台機能の充実、更に上質な音響の追求等、新たな歌舞伎座に相応しい機能の導入を計画しました。また、敷地の外に対しても木挽町通りの環境整備や明るい地下歩行空間の整備など周辺環境の充実も図りました。熱負荷の削減事務所は南側にコアを配置することで大幅な熱負荷の削減を図り、開口部についてもLow-Eガラス、竪庇の採用など、日射負荷の制御に配慮しました。ペリメータは窓台下よりブラインドと窓の間に給気するエアバリア方式を採用し、ブラインドBOXより排熱しています。自然エネルギーの利用事務所照明はセンサー調光による適正照度補正を行い、省エネに配慮しました。また10kWの太陽光発電システムを高層棟屋上に設置し、低圧系統連携を行っており、商用停電時には自立運転により小容量ながら臨時電源を確保できるシステムとしました。地下2階の木挽町広場は災害時の帰宅困難者受入れを想定しており、階段を利用した自然換気と太陽光発電により、停電時にも利用出来るよう配慮しています。設備システムの高効率化約1700㎡の事務室エリアを4ゾーンに分けて空調機を配置し、さらに約100㎡毎のVAVゾーニングにより空調を行っています。ペリメータのコールドドラフト対策として電気ヒータを設置し、外気温度による自動運転を行っています。オフィス系統空調機は全て外気冷房、CO2制御を導入し省エネルギーを図るとともに、熱量計によるエネルギー使用量の見える化を行っています。緑化低層部の劇場上部には屋上庭園を設け、5階の歌舞伎座ギャラリーとともに歌舞伎文化を発信しながら、さらにヒートアイランド対策にも寄与しています。地上部は木挽町通りの歩道を拡幅してシラカシやクロチクの植栽を行い、街路樹を片側から両側に増やしました。また街路樹が途切れていた晴海通りにもケヤキを列植しています。敷地北側区道に接道する部分には、高さ5ｍを超える壁面緑化を行い敷地の内外において環境改善とともに街並み景観の向上を図っています。Inheriting the pastGINZA KABUKIZA (Kabukiza Theatre + Kabukiza Tower) is a project to renovate one of the most beloved and iconic venues of kabuki, which has been performed at this location for 120 years.The project includes not only the Kabukiza but also the 29-story Kabuki Tower, which rises behind the theatre, and the underground Kobikicho Plaza, which connects directly to Higashi-ginza subway station. Together these additions have contributed to the regeneration of the Ginza district and created a new center for creativity and cultural communication. The plan for the new theatre called for inheriting the exterior design of the fourth-generation Kabukiza and preserving the interior conguration of the stage, audience, and lobby areas, while improv-ing the viewing experience, improving barrier-free access, enhancing restroom services, and strengthening stage functions, with particular attention paid to acoustics. The project extended beyond the site. It included improvements to the environment of Kobikicho-dori, a small street to the side of the theatre, as well as an inviting underground space for pedestrians.Reduction in heat loadA signicant reduction in the heat load of oces was achieved by placing the core on the south side. The direct sunlight load was controlled though the use of low-E glass and eaves over openings. An air curtain system was installed in the space between window and blinds. The air is supplied from beneath the window sill and exhaust heat is removed via the blind box.Use of natural energyOce lighting is controlled by sensors to ensure appropriate lighting levels and reduce energy use. A 10kW solar panel system was installed on the roof of the high-rise building. Working together with the low-power detection system, it provides a small but independently available emergency power supply during commercial power blackouts. The Kobikicho Plaza on the 2nd basement level was designed to accommodate stranded commuters during natural disasters. Natural ventilation via stairways and power from the solar panel system allow it to be used even during blackouts.Energy-ecient service systemsThe oce area, about 1,700 ㎡, is divided into four zones, each with an air conditioner. Variable Air Volume (VAV) is used to adjust air conditioning in zones of about 100 ㎡. Electric heaters are installed to counter cold drafts around the perimeter. The heaters are operated automatically according to the air tempera-ture outside. All oce air conditioning uses external air cooling and energy-sav-ing, low-CO2 control systems, with calorimeters to make total energy usage visible.Green improvementsThe low-rise theatre building has a green roof garden. Near the 5th-oor Kabukiza Gallery, a zone for communicating Kabuki culture, it also serves to mitigate the heat island eect. On the ground, the sidewalks of Kobikicho-dori were widened and planted with shirakashi oak trees and black bamboo, on both sides of the street instead of one. A row of Japanese zelkova trees was also planted along Harumi-dori, one of Ginza’s main avenues, where street-side greenery had been lacking. On the north side of the site, facing a city road, a green wall over 5 m high was created. These improvements inside and outside the site have beautied the neighborhood and enhanced the environment.1. 劇場天井2.木挽町広場3. オフィス窓廻り4. 屋上庭園1. Theatre ceiling2. Kobikicho Plaza3. Oce windows4. Rooftop garden4123協力：松竹株式会社・株式会社歌舞伎座Special Thanks : Shochiku Co., Ltd. / Kabuki-Za Co., Ltd.