Architecture 489 Christian Noble Structure Innovations 68 Commerzbank: A Sustainable Skyscraper Norman Foster Commerzbank: Frankfurt, Germany Norman Foster’s Commerzbank in Frankfurt, Germany is a testament to large-scale, sustainable urban structures. Combined with strict German laws for the work environment and the growing desire for sustainable urban architecture, Foster creates a piece that not only meets those requirements, but defines space not scene before in high-rise design. Winter gardens allow vast amounts of light deep within the building and provide pleasant views to those working deeper within the building. Operable facades create natural ventilation throughout the entire structure. Commerzbank, the tallest building in Europe, demonstrates that sustainable, energy concious design is possible at the scale of the skyscraper. Commerbank (Foster) Commerbank Perspective Rendering Architecture 489 Christian Noble Structure Innovations 69 Plan Development To provide the spaces and building layout necessary to create some of the sustainable features desired, an unorthodox plan was essential. Creating a central attrium space in a highrise building is not a simple task. First of all, the typical building layout includes a centralized core area for circulation, mechanical, and other basic building needs. To achieve this, the core functions were pushed to the outer corners of the building to make way for the atrium space. Typical Floor Plan (Buchanan) Site Plan (Buchanan) Architecture 489 Christian Noble Structure Innovations 70 Winter Garden Section (Buchanan) Section Development Development of the section was essential to the effort of building sustainability in terms of lighting and ventilation. Winter gardens had to be rotated around the facade of the building. This created voids in the sections and therefore long spans in each direction. The central atrium of the building was a major part of the sectional development. This space was free of structural members with the excetion of those used to frame the skylights which divide the building up into sections vertically. It was essential for there to be minimal intrusion into this space because it provided light both vertically, from the glass roof at the atrium’s top, and horizontally, from the winter garden facades to the office across the atrium. Building Section (Buchanan) Architecture 489 Christian Noble Structure Innovations 71 Structure Development To support the large spans of the winter gardens, special attention was paid to the structural system of the building. First of all, the triangular-shaped plan provided the rigid structural support only provided by an equilateral triangle. At each corner of this triangle, the cores are located. Here is provided the vertical load support for the entire structure. Eight floor deep, Verendeel trusses provide the structure to span the gardens between the core vertical load members. All of these strucutral elements wrapped around a central void allow the building’s structure to carry loads like a tube, a very efficient method for forming a structure. Massing Axonometric Tendering Structural Axonometric (Buchanan) Architecture 489 Christian Noble Structure Innovations 72 Natural, Central Lighting Lighting the interior of the building was a very important design factor. Since the offices in the building wrapped along both the exterior and interior facades, those on the interior needed to be provided with an ample exterior light source as per German law. This is provided all day long because the winter gardens are rotated around the building to capture light at all times of the day. June AM Shadow Diagram June PM Shadow Diagram Architecture 489 Christian Noble Structure Innovations 73 Natural, Central Lighting The diagrams on this and the previous page illlustrate the penetraion of light into the central space of the building’s atrium in the morning and afternoon during both summer and winter. When the sun is low in the sky, light penetrates the facades of the winter gardens. When the sun is higher, the glass ceiling at the top of the atrium allows light in which reflects back and forth throughout the entire core of the building. December AM Shadow Diagram December PM Shadow Diagram Architecture 489 Christian Noble Structure Innovations 74 Typical View from Deck (Buchanan) Winter Gardens The winter gardens in this building provide a great number of fuctions. One, the gardens provide a buffer zone of inulation between the central atrium space and the outdoors. Two, the stacked gardens allow for ventilation through the atrium which is divided into sections as the building goes upward. Winter Garden - Interior (Evans) Three, mass quantities of natural light are brought directly to the center of the building from its base to the top. Four, offices facing the center of the building are provided light and exterior views through the gardens. And finally, the garden spaces provide a much more green, natural space for those working in the building which is something lacking in the typical urban work environment. Winter Garden - Exterior (Evans) Winter Gardens (Evans) Architecture 489 Christian Noble Structure Innovations 75 Winter Gardens Massing Axonometric Architecture 489 Christian Noble Exploded Axonometric Structure Innovations 76 Architecture 489 Christian Noble Structure Innovations 77 Facade The design of the layered, operable facade on this project is central to the issue of sustainablity. These facades allow for ventilation on the scale of the office just as the winter gardens provide ventilation for the entire building. Strict German laws exist regulating employee comfort in the work environment. Aside from a well ventilated workspace, lighting is of great concern. Virtually all offices must have a window to provide light and a view outside. These facades provide that light in quantities sufficient to make the workplace pleasant. The drawing at the bottom is of the original facade design. Note that both intake of fresh air and exhaust of old air take place in the same area within the facade. The built design provides for the separation of these two making for much more efficient ventilation. Facade Light and Ventilation Diagram (Evans) Original Facade Design (Evans) Architecture 489 Christian Noble Bibliography Buchanan, Peter. “Reinventing the SkyScraper.” A and U. no 329, February 1998. 30-67. “Commerzbank-Zentrale in Frankfurt am Main.” Baumeister. May 1997. 18-27. Evans, Barrie. “Banking on Ventilation.” AJ Building Study. Februdary 1997. Foster, Norman and Partners. “Commerzbank.” http://www.fosterandpartners.com Structure Innovations 78
