2008年,為容納迄今為止最廣泛的德國戰后藝術的私人收藏——斯多赫收藏系列,庫普斯墨赫美術館(MKM)提出的擴建項目被提上日程。2013年,擴建項目在斯多赫家族的牽頭下啟動。赫爾佐格和德梅隆建筑事務受委托對當前條件下該場地的潛力進行了可行性研究,他們的成果將會帶給擴建項目一個全新的開始。最初的擴建思路是在筒倉塔頂建造一個發光的立方體,使之于遠處可見,現在被徹底拋棄了。取而代之的是,建立一座全新建筑,其材料和尺度依據碼頭沿岸的歷史建筑磚塊結構來呈現。新建部分以適宜得體的方式融入了碼頭建筑群,使既有的美術館綜合體成為了一個和諧優美的整體。乍一看,似乎新建筑一直都坐落在那里。
新建筑由三部分組成,三個體塊高度分別為33.5米、30.5米和27.5米。在體塊關系、建筑高度和材料選擇上,新建部分都充分參照了現有建筑,延續了它們的特征,并圍繞其建造形成了這個統一和諧的整體。新建三部分中的兩個結構為展覽空間,第三部分提供了通道,容納了公共設施和藝術品處理設施。擴建部分共計五層,其中一層在地下,建筑面積約為4 900平方米,此外還有大約2 500平方米的展覽區。
擴建部分的體塊關系受到“禁止在高速公路40米范圍內建造”法令的嚴格限制,故而對可用區域進行了充分的利用。展覽結構的安排——三部分中最高的部分和與之相鄰的較小部分——與無建筑控制區的形態相呼應,而第三部分的一個立面沿其邊界而建。項目額外的附加部分也是清晰可辨。在擴建部分的最高點,也就是最大展覽區域的最頂層,新結構的高度與現有的主要建筑維持在同一高度。
擴建部分將通過筒倉內的天橋在第一層和第二層與現有的展覽空間直接相連,方便來訪者暢通無阻地游覽整個美術館空間。相應地,新建展覽部分的高度也以現有的畫廊為參照。筒倉不僅被改造為連接新舊的關鍵要素,其內部也成為了一個獨特的展覽空間。考慮到筒倉是庫普斯墨赫美術館作為紀念性工業建筑不可或缺的雕塑性組成部分,項目對筒倉原有的材料進行了保留。長期以來,筒倉因其歷史和美學價值被世人所尊崇,如今,通過改造翻新,它還獲得了作為連接路徑和展示區域的全新功能。其內部的六個小型筒倉已被移走,隨著地面層屋頂的開放和聯通天橋的架設,整個空間都對來訪者直觀可見。同時,筒倉在美術館內的一些其他展覽區域也可以看到。
全新的展覽空間回應了庫普斯墨赫美術館作為19世紀和20世紀典型工業建筑設施的標志性特征。在建筑和室內設計上,畫廊空間都完美呼應既有的展覽區域。新建部分最頂層的展覽區,即無法從現有美術館空間直接進入的區域,由帶有頂部照明的棚屋結構圍合。所有的展覽空間都進行了多元化的靈活可變的操作考量。
筒倉配備加建的頂部建筑,仿佛他們自從1930年就佇立在這里。上層的加建部分有一個可以從碼頭長廊進入的觀景平臺,它將賦予筒倉另一個新的功能。
The extension project was activated in 2013, with the Stro?her family as clients. A feasibility study undertaken by Herzog amp; de Meuron explored the potential of the site under current conditions. The resulting project constitutes a radical new start. The original idea of an illuminated cube balanced on the silo towers and visible from afar has been jettisoned. Instead, we propose to erect a building whose dimensions and materials accord with the sequence of historic brick structures lining the dockside. The new structure thus completes the existing museum complex in a visually appropriate way and forms a suitable conclusion to the row of buildings along the dock. At first glance, it might seem as though the new building had always been there.
The new structure consists of three parts with a height of approximately 33.5, 30.5 and 27.5 metres respectively. In terms of mass, height and materials they take their cue from the existing buildings, continuing them and rounding them off to form a harmonious whole. Two parts contain the exhibition areas, the third provides access and houses utilities and art handling facilities. With five levels, one below ground, floor space amounts to some 4,900 square metres, in addition to exhibition areas of roughly 2,500 square metres.
Massing was crucially influenced by a ban on building within forty metres of the autobahn. Optimum use is made of the available area. The arrangement of the exhibition structures – the tallest of the three parts and the smaller one adjoining it – echoes the course of the building-free zone, while one elevation of the third part runs along its boundary. The additively composed parts remain distinctly legible. At its tallest point (the uppermost level of the larger exhibition component), the new structure is related in height to the main existing building.
The extension is to be linked directly to the existing exhibition spaces by bridges through the silos at the first and second upper levels, facilitating uninterrupted visitor access throughout the museum. Similarly, the height of the new exhibition areas takes its cue from the existing galleries. The silos will not only be converted into elements connecting the old with the new; they will also house distinctive exhibition spaces. Their original materials are to be retained, however, because the silos are an indispensable ‘sculptural’ component of the Ku?ppersmu?hle as an industrial monument. Long reduced to this historical and aesthetic aspect, they acquire a new function through refurbishment as access links and display areas. Six inner silos had already been removed. Now, with the ground-floor ceiling opened up and the insertion of the bridges, the entire space will be visible to visitors. In addition, the silos can be seen from some of the exhibition areas.
The new exhibition areas echo the overall additive character of the Ku?ppersmu?hle as a typical industrial facility of the nineteenth and twentieth centuries. In their architecture and interior design, the galleries echo the existing exhibition spaces. The uppermost display area, which is not directly accessible from the existing building, consists of a visible shed construction with top-lighting. All exhibition levels have a spatial arrangement facilitating flexible multiple uses.
The silos are to be fitted out with a superstructure, as they were original, in the 1930s. Featuring a viewing platform accessible from the dockside promenade, the superstructure will grant the silos yet another new function.