ctbuh.org/papers Title: Historical Evolution of the Service Core Author: Dario Trabucco, Research Fellow, IUAV University of Venice Subject: Architectural/Design Keywords: Adaptability Service Life Sustainability Publication Date: 2010 Original Publication: CTBUH Journal, 2010 Issue I Paper Type: 1. Book chapter/Part chapter 2. Journal paper 3. Conference proceeding 4. Unpublished conference paper 5. Magazine article 6. Unpublished © Council on Tall Buildings and Urban Habitat / Dario Trabucco Historical evolution of the service core "The service core is a distinctive feature of a tall building and its design plays an important role in the success and sustainability of the whole structure." Dario Trabucco The service core is the distinctive feature of a tall building: it provides the skyscraper with Author structural solidity, room for elevators, toilets, and other amenities, and constitutes the main Dario Trabucco , IUAV University of Venice, Italy network for utility services, power and data. Though many of these elements were present Università IUAV di Venezia even in the very first examples of this building typology, the actual service core is the result of DCA, Dorsoduro 2206 30123 Venice, Italy an evolutionary design process that has taken more than one hundred years and is still t: +39 347 4161732 evolving. The present paper examines the designs from the early skyscrapers of Chicago and e: [email protected] Manhattan, through the zoning restrictions and the technological innovations of the post- Dario Trabucco World War II period, to the present modern control procedures of the elevators. The role of the Dario Trabucco is an architect and contract professor of service core has always influenced many aspects of the whole design of tall buildings building technology at the IUAV University of Venice, Italy. He recently concluded a PhD in building concerning the structural system, the access/egress strategies and sometimes even their technology with a thesis on the design of the service shape. The future trends for the evolution of the service core are mentioned including the core of tall buildings. His research activity is now focussed on the relationship between this element and innovative design strategies adopted in some recent skyscrapers. the running consumption / embodied energy of a tall building. The Early Years of the Tall Building the first two were so long inseparable.” As it can be The first buildings that surpassed the 6-story seen in this statement, two technical reasons threshold quickly started to define new (the possibility of building tall and the possibility standards of spatial design that partly changed to make the high levels easily reachable) are the architectural traditions determined in the jointed with a third , which is the consequence previous centuries: not the magnificent of safety concerns (fireproofing floors, in order staircase of the renaissance palazzo but the to make the building safe). In fact, it should be elevator core became the focal point of the noted the singular coincidence that many tall building (Hill, 1893). buildings rose on the same plots of previous buildings, completely burnt in disastrous fires In order to understand the evolution of the (Weisman, 1970). ...adaptive reuse service core, it is necessary to retrace the origins of the tall building typology, stemming from However, the key feature that made tall two American cities: New York and Chicago. buildings possible was the elevator, since many It’s really challenging masonry tall buildings rose before the to convert an office building Even though the Home Insurance Building is “ often considered the first skyscraper, the origin acceptance of metal skeleton structures (one into a hotel. The Foshay of this building typology is still disputed by example is the Monadnock building in project says something about many (Condit 1960, Mujica 1930; Schuyler 1961, Chicago). The role of the elevator was so Weisman 1970). Despite this, it is commonly important that the first descriptions of such adaptive reuse and the new typology refer to them as “elevator-building” importance of saving a agreed that tall buildings required the presence of the following elements in order to be feasible; or “elevator-architecture” (Unknown, 1895) beautiful existing building. an author described the rise of skyscrapers in Despite the common basic ingredients, it must ” the moment it happened (Fryer, 1891): “Today be emphasized how the initial evolution of the Lucien Lagrange, principal of Lucien there is simply no limit to the height that a building tall building typology led to the distinction of Lagrange Architects discussing the challenge can be safely erected. This result has been reached two completely different organizational of the Foshay project. From ‘Monumentally mainly through three inventions, all of which are schemes (a slender tower or the “quarter Hip Hotel Conversion’ ,Building Design and distinctively American: 1) the modern elevator; 2) blocks”), linked to the historical and urban Construction, September 2009, pp 14-15 the flat-arch system for fire-proof floors; 3) the characteristics of the two cities, New York and skeleton construction. The last enumerated one Chicago, where they developed. has only lately joined the combination in which 42 | Historical evolution of the service core CTBUH Journal | 2010 Issue I Figure 1. The Trinity and the US Realty Buildings have a long bank of elevators disposed on one Figure 2. Proposed building for New York. The side of the corridor Architectural Record Vol. 2. April-June, 1893. n° 4. The tale of two cities: New York and Chicago The second type varied remarkably in buildings Buildings of impressive dimensions could then New York: Since 1892, when the utilization of that occupied the entire depth of a city block. In be built, precisely called “quarter blocks” (see metal structures was approved by the building this case, the greatest depth determined the Figure 3). code of New York, the height of office buildings distribution corridor. On one side, elevators Such buildings were about 50 x 50 meters in began to exceed 16 floors on a regular basis. were organized in a long row, sometimes up to plan and their height was limited by regulations The first tall buildings were laid out on long 12 to 14 cars in a row. Also in this case, the much more strict than those enforced in New narrow lots, 20 to 30 meters wide in front, central disposition allowed an optimal York. During the first decades of the 1900’s, stretching for the full width of the Manhattan exploitation of the building’s perimeter area, building regulations fixed the maximum grid (60 to 70 meters) in depth. However, there guaranteeing sufficient natural illumination on building height between 45 and 90 meters. are examples of smaller lots, corresponding to the working side of the spaces (Osterhaus, These limits led to erecting massive structures, about half of a block. The shape of the lots was 1993) (see Figure 1). in some cases perfectly cubical, which had to interpreted by architects in two different The central position of the vertical exploit the building opportunities imposed. The organizational schemes, based upon the communication center was a representation of construction of office spaces, as proof of the internal traffic system. a norm, but not a rule. In a few designs, some speculative value of skyscrapers, was The first type designed the buildings on almost conditions suggested a different organization of determined in a precise way: "the ideal office is square-shaped parcels with a system of 4 to 6 the vertical traffic system, such as the possibility 5,5 x 7,5 meters (18 x 25 feet in the original text, elevators commonly located in a central for the building to be flanked by another note of the author). The fenestration should be position, with offices opening directly into this neighboring structure along its entire height. In arranged so that it would be possible to subdivide central area of communication. The short such a case, the vertical traffic system would the 5,5 meter long (18-foot long) office unit in two central hall, about 2.5 meters wide, was flanked have found itself again, considering both parts to provide two small offices, each with a by elevators that took up an additional space of buildings, in the central position (see Figure 2). window, and in the back of the two offices 2.5 meters on each side. A corridor allowed The location of the other practical-use spaces direct access to the offices located around the necessary for the building (restrooms, electrical central unit. The typical core-to-wall distance closets and vertical ducts) varied from case to had a maximum depth of 8 to 9 meters, which case. They were usually placed in a peripheral corresponded to the optimal distance beyond position, so as to be easily ventilated, occupying which natural light, coming from the windows, the less lucrative zones of the building. was too weak to allow workers to carry out their activities. At this time, electric and gas lamps still had very poor efficiency. The sum of widths, Chicago: At the same time, the architectural calibrated on this construction and functional experience taking place in Chicago created "optimum", gave a total measure of about 25 completely different results. The grid on which meters, which corresponded to the average the city was planned was formed of large, width of a lot. Such configuration recurred also almost squared blocks about 100 x 100 meters in the depth of the building, with the most wide. Such a condition, combined with the appealing offices behind the main street façade. city’s vicissitudes (amongst which the Great Fire of 1871), made large lots possible, often corresponding to an entire quarter of a block. Figure 3. Railway Exchange Building, Chicago. A “quarter Block”.