L’Observatoire de ZI-KAWEI locates at the south of the Xujiahui Cathedral, separated by a lawn, and the Tome of Xuguangqi is just not far away at its west. The observatoire was built at the west bank of the Puhuitang River in 1873, expanded at the original location in 1880 and further expanded with new buildings 100 meters west to the original site in 1900.
L’Observatoire de ZI-KAWEI was originally a masonry-timber three-stories building with a symmetric layout of five lateral zones, featuring a gallery as a wider corridor in the north part. There was a 40m high masonry-timber bell and wind tower on the gate of the second floor originally and in 1908-1910, the wind tower was replaced by a 35m high steel tower due to the bearing problem of the base and then the steel tower was removed in 1963. The facade consisting of grey and red bricks is constructed in three vertical zones. The window has an arch frame and hard wood blinds. The roof is a double-pitch type with its gable ends tucked inside, forming a unique trapezoidal gable. L’Observatoire de ZI-KAWEI is an early archaistic building, a typical style of Shanghai modern church architecture. Particularly its central lofty tower which has a mannerism style of late renaissance was used for wind measurement. Now the L’Observatoire de ZI-KAWEI is one of the fourth batch of heritage architecture in Shanghai as well as a municipality protected historic site.
After many times of renovation and reinforcement, the main structure of the building has turned to be a hybrid one of masonry, timber, steel and concrete.
Since 2013 along with the commencement of the integral regeneration of Xujiahuiyuan area, which is the central of Xujiahui, the refurbishment of L’Observatoire de ZI-KAWEI has also been put on the agenda. Based on the principle of authenticity, reversibility and recognizability, the refurbishment will be carried out in the following aspects:
1.restore the brick wall of the facade and remove the latest coatings with minimum strength; peel the latest covered stone-style cement rendering of the bell tower; recover the big clock face of the bell tower and the steel tower on the original bell tower; repair the wood doors and windows on the facade and recover the wood blinds; remove firefighting stairs and various pipelines on the facade.
2.repair the additional part built in the past years, retain the previous renovations basically and remove the additional part which has affected the overall style of the building, for example, additional second-floor platforms at both sides of the bell tower on the northern facade, in the hope of harmonious style of the whole building; retain the reinforcement, replacement and addition of structural components in the previous renovations, for example, in the interactive space at both east and west of the ground floor, expose and display the wood pillars, brick pillars and concrete pillars of different periods and styles in the entire space within the demolished partition walls to show the historic transformation of the building with the exposed original timber grille ceiling after removal of the suspended ceiling. The large spaces at both east and west of the third floor does not only have exposed wooden truss but also retain the joist steel girder reinforcement structure under the roof truss.
3.the renovated L’Observatoire de ZI-KAWEI will integrate more space for meteorological science exhibition, book browsing, interactive experience, etc. based on the original functions of observation business and weather forecast. The central part of the ground floor remains to be used for meteorological observation while the large rooms at both east and west are served as interactive experience space. The whole layout of second floor is used for meteorological science exhibition while the large halls at east and west connected with small gallery style rooms. The large spaces under the pitched roof at both east and west of the third floor are used as interactive broadcast room and reading room respectively and there is a spiral stair to connect the reading room with the exhibition room on the second floor. The interlayer space under the roof of the fourth floor will be transformed into astronomical classrooms connected with centered archways.
4. remove the partition walls at east and west sides to restore a large space; considering the added concrete stair unable to be removed, restore the gallery space at the eastern section of the second and third floor to try to restore the axially symmetrical classical space order, making L’Observatoire itself a display object.
5. after removing the added outdoor fire escape, considering the original indoor wood stairs are unable to be restored, add a steel-timber stair at the opposite of the original stair on the east for escape and then re-design the circulation for exhibition and administration.
6.after many times of renovation, the austere and concise historic style inside L’Observatoire has been damaged, so this refurbishment will re-shape the indoor space based on new program. All the indoor original wood truss and wood grille ceiling will be exposed to a maximum degree; the exhibition room on the second floor will be re-shaped into a display environment full of contemporary elements based on the stripped brick wall combined with newly designed display walls and racks; the public area like entrance and gallery will apply the hexagonal mosaic pavement similar to those debris found in the restoration site, with the historic style echoed by the contemporary approaches such as simple white walls, picture rails and shallow dome ceiling light troughs.
7.Repair the damp-proofing of the wall on the ground floor; improve the roof insulation and waterproof performance; add fire sprinklers, hydrants and fire alarm system; apply VRV air-condition and ventilation system; improve the drainage and electrical system.
Atelier Z+ is managed by the two principal architects, ZHANG Bing and ZHOU Wei. ZHANG Bin was born in Shanghai in 1968. He obtained Bachelor and Master degree of Architecture in College of Architecture and Urban Planning, Tongji University respectively in 1992 and 1995. From 1995 to 2002, he was the lecturer in College of Architecture and Urban Planning, Tongji University. Being selected in the program of “150 Chinese Architects in France”, he studied at L’Ecole d’Architecture Paris-Villemin from 1999 to 2000 and also worked for Architecture Studio as a visiting architect for that period of time.In 2002, he established Atelier Z+. In 2004, he was invited to be a member of the Jury for College of Architecture and Urban Planning, Tongji University. ZHOU Wei was born in Shanghai in 1972. She obtained Bachelor degree of Architecture in College of Architecture and Urban Planning, Tongji University.In 2003, she joined Atelier Z+ as a principal architect.