(Student’s Full Name)
According to John Arend, Mike Benkert, Audrey deFilippis and Saretta Tillmaand, when the Commerzbank building opened its doors in 1997, the “53-story” edifice became the one of the “tallest” buildings located in Europe (1). Nevertheless, the edifice’s distinctiveness did not come from its height, but, rather, it came from the way in which it combined “form, inventiveness, and technical expertise” (Arend, Benkert, deFilippis, & Tillmaand 1). The design and construction of the Commerzbank saw the “[b]reaking away from the American model of deep-planned, air-conditioned structures” that have a “central service core” (Arend, Benkert, deFilippis, & Tillmaand 1). This building, which was designed by Sir Norman Foster, became an example of how sustainability can be interlinked with technological innovation. The same can be said of other buildings that Foster designed both before and after the construction of the Commerzbank. These include the Gerkhin in London, the Century Tower in Tokyo, Torre Caja in Madrid, The HSBC Headquarters in Hong Kong and Faisaliah Tower, Riyadh. Based on evidence provided during research it can be argued that the Commerzbank building borrows some elements from previous projects and inspired later projects designed by the architect. Therefore, in light of this fact, it can be argued that the Commerzbank building in Frankfurt represents a turning point in the architect’s body of work, as it pertains to sustainable systems and energy efficient designs. This is because the architect relied on the use of specific of materials and unique design features that were inspired by previous buildings and were the source of inspiration in other edifices designed by the architect.
Scholars contend that the Commerzbank building was a successful representation of the “humane and socially responsible skyscraper” (Arend, Benkert, deFilippis, & Tillmaand 1). The edifice was created to provide “natural ventilation,” which is facilitated by the “design of the layered, operable façade” and the “winter gardens” (Noble 77). The winter gardens ventilate the “entire building” by allowing the circulation of air through the “atrium,” which is “divided into sections as the building goes upward” (Noble 74). On the other hand, the “layered, operable façade” ventilates the various offices within the whole building (Noble 77). It does by separating the “old air” and “fresh air” unlike the “original façade design” that allowed both the “old air” and the “fresh air” to be circulated in the same area (Noble 77). This design ensures that occupants within the building will not find it necessary to use artificial forms of ventilation.
It should be noted that the design of the Commerzbank building facilitates the influx of natural light inside the edifice. Noble explains that large quantities of “natural light” enter the building by way of the winter gardens that allow the “natural light” to be “brought directly to the center of the building” from its “base to the top” (Noble 74). When this happens, “offices facing the center” of the edifice are given access to light as well as “exterior views through the gardens” (Noble 74). In addition to the winter gardens, the building’s façades facilitate the influx of light into the building’s center. Noble mentions that when the “sun is low in the sky,” light enters through the façades where the winter gardens are located (73). However, when the sun is “higher” in the sky then the “glass ceiling at the top of the atrium allows light” to be reflected “back and forth throughout the entire core of the building” (Noble 73). Therefore, it is clear that the façades of the building along with the winter gardens allow the occupants of the building to not rely on artificial lighting while inside the building.
It should be noted that when one studies the features of the HSBC Building of Hong Kong, which was “completed in 1986,” one will find that Foster had played with the idea of using glass to facilitate the inflow of natural light inside of a building (Wainwright par.5). Oliver Wainwright explains that Foster used a “revolutionary mechanical ‘sunscoop’” to flood natural light into the edifice (Wainwright par. 14). The writer explains that there is a “bank of mirrors” that “projects out on the south-facing façade at 12th floor level” (Wainwright par. 14). This “‘mechanical ‘sunscoop’” is “programmed to follow the position of the sun throughout the day” and “reflect the light back onto a curving mirrored ceiling at the top of the atrium” (Wainwright par. 14). This reflected light will most obviously flood the interior of the building. However, this feature, which is an example of a sustainable system, is not used by those who occupy the building since they switch the “office lights” on during the day (Wainwright par. 14).
Furthermore, it should be noted that in designing the HSBC Building, Foster allowed the “mast structure,” which allowed the building to resemble a bridge, to push the “service cores to the perimeter so as to create deep plan floors around a ten-story atrium” (Pagnotta par. 4). As in the case of the Commerzbank Building, the atrium is not only important in bringing light to the interior of the building, but also to ventilate the inside of the edifice. However, the HSBC Building differs from the Commerzbank in that there is no attempt made by the architect to ensure that individual offices are naturally ventilated.
Nevertheless, the HSBC Building shares some similarities with the Commerzbank as it pertains to architectural innovation. Foster used “pre-fabrication” to construct “over a million square feet of office space in a short amount of time” (Wainwright par. 7). It was the use of this method of construction that made Foster one of the “titans” of the “High Tech movement” (Wainwright par. 7). This method involved the assembling of parts from various parts of the globe, including Scotland, Japan, Germany, Holland, Italy and the United States.
Additionally, it should be noted that the HSBC building was designed to “provide flexibility for future changes” (Wainwright par. 10). Pagnotta mentions that the “flexibility” of the building’s design facilitated the reconfiguration of “office layouts with ease” and “incorporating a large dealers room into one floor” (par. 7). Flexibility is an important concept as it relates to sustainability because proponents of sustainable architecture argue for the reduction of the “suburban sprawl” and the prevention of the additional loss of “green” spaces in urban areas (Wood 403). Wood contends that sustainable architecture will promote the concentration of “higher numbers of people on smaller plots of land” within very tall buildings (403). When the HSBC building facilitates the integration of offices into the building’s design rather than forcing the owners of the building to demolish the edifice or build another edifice nearby to accommodate additional offices, land space can be saved when the design of the building allows additional office or other room spaces to be integrated within the current design of the HSBC building. Therefore, in light of this fact, it can be understood why Foster decided to allow the Commerzbank to be the one of the “tallest” buildings in Europe (Noble 68). The architect might have made this decision so as to ensure that a significant amount of green space was not used up by the building. However, it should be noted that there was no clear attempt made by the architect to make the building flexible.
The Gherkin in London (which was completed in 2004), as pointed out by Marianne Freiberger, was created to be “as sustainable a building as possible” (3). Therefore, in that regard, this building shares similarities with the Commerzbank in Frankfurt, Germany. In order to make the building sustainable, the architect had to choose a shape that would maximize “natural air ventilation” and the “influx of natural sunlight” (Freiberger 3). Freiberger explains that “six triangular wedges were cut of the circular plan of each floor” while “penetrating deep into the building’s interior” (3). The writer mentions that these wedges function as “light wells,” and the “shafts” created by these wedges “increase natural ventilation” (Freiberger 3). Additionally, is should be recognized that there are “dark spirals of glass to spread natural light” behind the “six lightwells” (White par. 5). It should be noted that each floor of the Gherkin rotates “[f]ive degrees” from the one below it (White par. 6). When this happens then the triangular wedges and shafts “spiral up the building” and “interact optimally with the air currents caused by the building’s outward shape” (Freiberger 4). The windows located in the “façade of the wedges open automatically” and “draw fresh air into the building” (Freiberger 4).
Furthermore, it should be noted that Foster uses in the Gherkin “perimeter diagonals” or “‘diagrids’” for “structural effectiveness” and “esthetics” (Moon, Connor, & Fernandez 205). Moon, Connor, and Fernandez explain that “diagrid structures,” such as the Gherkin, are able to withstand forces that are going in “windward” and “across-wind directions” (206). The use of “diagrids” is especially useful when constructing very tall buildings, such as the Gherkin, that has to cope with “static loads” and “dynamic loads” (Moon, Connor, & Fernandez 206).
The Commerzbank building, on the other hand, does not have diagrids located on its exterior but it has a “triangular-shaped” structure (Noble 71). This “triangular-shaped” structure of the building provides a “rigid structural support” (Noble 71). In addition to the triangular-shaped structure, “cores” are located at the “corners of the triangle” so as to provide “vertical load support for the entire” building (Noble 71). Moreover, as explained by Arend, Benkert, deFilippis, and Tillmaand, the building is based on the design principles of the “Vierendeel” frame (3). In the “Vierendeel” frame is “made up of eight horizontal and four vertical elements” work together to “distribute loads equally” and “absorb lateral forces in rigid moments” (Arend, Benkert, deFilippis, & Tillmaand 3). The “Vierendeel” frame allows the Commerzbank building to support both “gravity loads and wind loads” (Arend, Benkert, deFilippis, & Tillmaand 3). Additionally, the columns created by the “Vierendeel” frame have an added benefit as it pertains to sustainability. The “corner columns serve as circulation space” between “floors,” thus further reducing the need for means of artificial ventilation (Arend, Benkert, deFilippis, & Tillmaand 4).
The Century Tower in Tokyo, which was completed in 1991, is another high-rise building that relies on the use of an atrium, as is seen in the design of the Commerzbank building, to facilitate the penetration of natural light and the circulation of air. The building is designed to be “nineteen to twenty stories high” linked by a “narrow atrium” (“Century Tower,” par. 10). The building has “smoke-activated baffles” that are activated during a fire to “descend from the main and mezzanine floors” to “accelerate air-flow from the atrium into the affected floor” (Foster + Partners 2). Foster saw the need to integrate these “smoke-activated baffles” in the design of the building because the Japanese government prohibited the combination of “open office atria with open-access floor space, due to fire regulations” (Foster + Partners 2). Another architectural innovation that was a part of the design of the Century Tower is the exterior of the buildings being “eccentrically braced by frames,” so as to protect the building from severe damage during an earthquake or typhoon, which is a common occurrence in the city where the building is located (Foster + Partners 2). Therefore, it is clear that the architect allowed the conditions of the climate of this region of the world to influence the manner in which he designed the building, and determine what technological innovations will best suited for the Century Tower.
Likewise, technological innovations, which were influenced by the climate conditions of a region, have been integrated in the design of the Commerzbank Tower by Foster. In designing the tower, Foster takes advantage of the temperate climate by using “passive strategies for heating, cooling, and ventilation” of the Commerzbank offices throughout the year (Arend, Benkert, deFilippis, & Tillmaand 10). The architect used a “cladding system by utilizing double skin glazing” with “ventilated cavity spaces, operable casements, and Venetian blinds” (Arend, Benkert, deFilippis, & Tillmaand 10). This means that when “heating is required” during the summer months in Frankfurt, “exterior vents are closed to allow heat to build up in the cavity spaces” (Arend, Benkert, deFilippis, & Tillmaand 10). This is important because it helps to protect against the “cold winds while improving the thermal insulating properties of the windows” by up to “20%” (Arend, Benkert, deFilippis, & Tillmaand 10). However, when “cooling is required” in the summer months the “cavity vents and operable casements are opened to allow for natural ventilation” (Arend, Benkert, deFilippis, & Tillmaand 10). When this happens, “cool air” enters low vents and “warm air” exits through high vents “after circulating through the office” (Arend, Benkert, deFilippis, & Tillmaand 10). In addition, the “Commerzbank offices” employ the use of “radiant floor heating” to “effectively warm objects instead of air” during the winter months (Arend, Benkert, deFilippis, & Tillmaand 10). In the summer months, the building’s offices rely on the use of “chilled (water) panel ceilings” to “cool the space in a more energy-efficient” way compared to the “forced air alternatives” (Arend, Benkert, deFilippis, & Tillmaand 10).
Admittedly, there are not many features that the Century Tower has that are related to sustainability. However, it should be noted that the building facilitates “mixed-use functions,” thereby promoting “social sustainability” (Wood 403). The Century Tower houses a “cave-like museum,” “tea house,” “restaurant,” “health club,” and “pool” (Wood 403). Similarly, the Commerzbank building functions as a mixed use building by housing “shops, carparking, apartments and a banking hall” (Arend, Benkert, deFilippis & Tillmaand 1). In addition, the heart of the tower contains “restaurants, cafés and spaces for social and cultural events” (Arend, Benkert, deFilippis, & Tillmaand 1). Arend, Benkert, deFilippis and Tillmaand mention that the inclusion of all of these various spaces help to connect the Commerzbank to the “broader community” (1).
The Torre Caja or the Torre Cepsa in Madrid, Spain, which was finished in 2008, is another example of a sustainable building that was inspired by elements found within the Commerzbank Tower. For instance, the building has a “unifying curtain wall system” that are made of “triple glazed units” with a “solar protective coating” (“Torre Cepsa” par. 1). Similarly, the Commerzbank Tower does have a “solar protective coating” or “double-glazed glass curtain wall” to protect the building from the glare of the “hot summer sun” (“Torre Cepsa” par. 1; Arend, Benkert, deFilippis & Tillmaand 5). In addition, the Commerzbank Tower has “shading devices” that are “sandwiched between the double-glazed curtain wall” (Arend, Benkert, deFilippis & Tillmaand 5). It should be acknowledged that the winter gardens glazing system of the Commerzbank building has “hollow trusses” that are “filled with water and connected to the building’s heating system” (Arend, Benkert, deFilippis & Tillmaand 5). This allows the winter garden glazing system to be transformed into “large radiators” for the winter gardens and ensures that “condensation and down drafts do not occur in the atrium” during the winter (Arend, Benkert, deFilippis & Tillmaand 5).
The top of the Torre Caja is reinforced so as to withstand “wind impact” and is designed to “house wind turbines as a possible future innovation” (“Torre Cepsa” par. 1). On the other hand, the Commerzbank building does not have an area to “house wind turbines,” but the building is designed in a particular way to ensure that it is able to withstand winds, as mentioned previously. It should be acknowledged that the Commerzbank Tower has a “perforated tube structure” (Arend, Benkert, deFilippis & Tillmaand 8). This “perforated tube structure” consists of “Vierendeel trusses” and the “corner columns” (Arend, Benkert, deFilippis & Tillmaand 8). These elements are important because they help to “resist lateral wind loads” and add “stiffness and stability to the structure” (Arend, Benkert, deFilippis & Tillmaand 8).
Moreover, the Torre Caja has the flexibility to be “partly sublet” so that the building can be easily expanded or contracted “in the future,” if it is necessary to do so (“Torre Cespa” par. 2). As mentioned earlier, there was no deliberate attempt made by Foster to make the Commerzbank building flexible in its design so that it could accommodate a reconfiguration of the office spaces. On the contrary, inflexibility appears to be a major feature in the Commerzbank building. Foster ensures that the Commerzbank building is inflexible by allowing the “columns, Vierendeel frames, and link frames work together to form a structure” of “greatness and stability” (Arend, Benkert, deFilippis & Tillmaand 2). Wood explains that “lateral stiffness” is desirable for very tall buildings since it will ensure that “static and dynamic loads” are handled well by the structure (Wood 206).
A prominent feature of the Torre Caja is the “north-south orientation” which maximizes “natural shade by directing the low angle sunlight” to the core of the building, where the offices are located (Foster + Partners 2). Likewise, the Commerzbank building is designed to bring natural light to where the offices are located. However, it does this by way of three features: gardens, the atrium, and the glazing system.
The Al-Faisaliah Tower, located in Riyadh in Saudia Arabia, was completed in 2000. This building, like the Commerzbank, functions as a sustainable building. It has anodized “aluminum panels with large cantilevered sun shading devices” (“Al Faisaliah Tower” par. 9). These features help in minimizing “glare and allow the use of non-reflective, energy efficient glass” (“Al Faisaliah Tower” par. 9). As mentioned earlier, the Commerzbank has the winter garden glazing feature to minimize glare from the sun’s rays.
The Al-Faisaliah Tower adheres to the principle of “social sustainability” by allowing the building to “mixed-use functions” by housing the following: centerpiece “office tower,” “the 5-star Faisaliah hotel,” “a banqueting and conference” center, “shopping mall,” and “luxury apartments” ( “Fosters and Buro in Possible Riyadh” par. 2).
Foster when designing the Al-Faisaliah Tower, he allowed the building to be square “in plan” with the edifice being “designed around a compact central core which tapers to a point” (Foster + Partners 1). Furthermore, there are “four main corner columns that define its unique silhouette” (Foster + Partners 1). Therefore, the tower differs from the Commerzbank building since its plan is “square” instead of triangular (Foster + Partners 1). The square plan, like the triangular plan, helps to provide stability for the very tall building (which is 267 meters high). However, it has “corner columns” like the Al-Faisaliah Tower but there are two columns located at each of the three corners of the building totaling 6 columns in all (Foster + Partners 1). The corner columns in the Commerzbank building allows the building to cope with “wind loads” (Arend, Benkert, deFilippis & Tillmaand 11). Hence, this point will cause one to conclude that the “four main corner columns” help to withstand the “wind loads” that very tall buildings, which are improperly designed, are usually susceptible to (Arend, Benkert, deFilippis & Tillmaand 11). Furthermore, the four main columns of the Al-Faisaliah Tower adds to the aesthetic appeal of the building. Similarly, the Commerzbank’s six columns help to add to its distinctiveness as it stands on the Frankfurt skyline.
In addition, the Al-Faisaliah Tower is another example of how Foster integrates the concept of flexibility within his projects. This “high degree of flexibility” of its interiors is “achieved by a unique long-span arch system” (Foster + Partners 2). This helps to provide a “column-free space” that is “57 meters wide and 81 meters long,” with a “moveable partition system that can divide the hall” into a “maximum of sixteen separate rooms” (Foster + Partners 2). As mentioned earlier, there is no attempt made by the architect in his design of Commerzbank Tower to make the building be flexible to the point that the office spaces can be reconfigured. However, as indicated previously, the architect was more concerned with ensuring that the Commerzbank building could handle forces from winds and “gravity loads” (Arend, Benkert, deFilippis & Tillmaand 11).
Furthermore, Foster integrated elements within the design of the Al-Faisaliah Tower that hearken back to the “Islamic culture” (Foster + Partners 2). The architect placed a colored “glass wall,” which was created by the “artist Brian Clarke” (Foster + Partners 2). This “glass wall” references pictures from not only the “Islamic culture,” but also images from the “Riyadh’s desert” (Foster + Partners 2). Chris Abel and Norman Foster point out in their book, Architecture and Identity, that it is possible to allow “tradition and modernity” to be harmonized in the same architecture (124). Clearly, the manner in which Foster has designed the Al-Faisaliah Tower has proven that this can be done. The architect is mindful of the fact that elements of the culture in which the building is constructed needs to be represented so as to ensure that individuals living in and around the edifice can feel as though their cultural identity has significance as it pertains to the design of the building.
When assessing the design elements of the Commerzbank building, it was noted that there were spaces within the “heart” of the building that contains spaces reserved for “cultural and social events” (Arend, Benkert, deFilippis, & Tillmaand 1). It can be assumed that when Foster decides to reserve such cultural and social spaces in the core of the Commerzbank building, he is not only allowing the edifice to play a central role in the “broader community,” but he is also using architecture to affirm the cultural identity of the persons who live in or nearby the building.
In conclusion, based on a careful assessment of the elements and features of the Commerzbank building in relation to five other global examples, it can be argued that the Commerzbank building represents a pivotal point in the architect’s body of work, as it relates to sustainable systems and designs. This is the case because the Commerzbank building symbolizes an almost perfect union of technological innovations and sustainability. In some of his projects, Foster featured more elements of technological innovation compared to features relating to sustainability. The Commerzbank building is a successful representation of a sustainable building because it limits as much as possible the use of artificial lighting and ventilation. Furthermore, the design of the Commerzbank Tower placed emphasis on social sustainability, the cultural identity of the people of Frankfurt, and the reduction in the use of land space in an urban area.
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