Architecture and Density

If we want density, FOR MOST OF their history, cities have tended to be dense, with relatively is going up the only way? tall buildings a key feature. The attacks of 9/11 struck at the notion that density and tall buildings are desirable. In the wake of the collapse of the World Trade Center towers, many people claimed that terrorism spelled the end of the sky- scraper. But density is a primary feature of the twenty-first century. The megacities of the global south, from Bombay to São Paulo, are growing ever larger and denser. Density also matters in places with global telecommunications and global networks, whether London or City. Today’s leading economic sectors need

SASKIA SASSEN access to “thick” environments; that is,

4 ZELL/LURIE REAL ESTATE CENTER REVIEW 5 places that are dense with communications world. This is the case not only in percent, though much of this is not top- and for new firms to seize the opportunity and talent, massive concentrations of Shanghai, with its 3,000-plus new high- quality office space. to move to . This has buildings, and infrastructure. In such rise buildings over the last five years, but It is important to remember that already happened with new media compa- places, tall buildings are both functional also in London, where the new “plan,” complex cities, like , con- nies, which benefit from the intense prox- and emblematic. proposed by developers and accepted by tinuously reinvent themselves to enable imity to multiple types of expertise and Critics of dense concentrations of high- the mayor, is to build 70 new tall build- new types of leading economic sectors to resources (financial, legal, accounting). rise buildings argue that urban density is ings. The last such massive building pro- emerge. The demise of Wall Street has These firms, which operate in highly spec- no longer beneficial for firms and markets, gram in London took place in the 1960s been predicted many times, most recently ulative and globalized sectors, need thick as the existence of global telecommunica- and early 1970s, with the building of the in the early 1980s, when the departure of environments and have thrived in Lower tions and networks has changed the rules Telecom Tower, Millbank Tower, Euston large commercial banks and insurance Manhattan. So will a whole new category of the game. Globalization and informa- Tower, London Bridge Towers, Nat West companies—and a devastating financial of firms that cannot even be foreseen at tion technologies are meant to allow Tower, and the Barbican. In New York crisis—convinced many that Lower this time because they will be part of new economic activity to happen at a global City, even after the September 2001 Manhattan was finished as a financial cen- sectors that mix different types of expertise scale, or in electronic markets that are attacks, vertical development continues. ter. But these departures created room for and resources—hybrids that will become divorced from specific places. Clicks have For example, the six World Trade Center what were then relatively small financial the norm in the future. Whatever form the replaced bricks. reconstruction project finalists all included firms to grow and take over functions from revival of Lower Manhattan takes, there is If these arguments are true, one extremely dense—and tall—buildings. the large banks. Today, the departure of little doubt that tall buildings will play a might wonder about the verticality and However, skeptics point to the high many area firms to Connecticut, New major role, because strategic, creative activ- density that is still the dominant form of vacancy rate for office space in Lower Jersey, and Midtown Manhattan may well ities—whether economic, cultural, or urbanism in many cities around the Manhattan, which is today about 17 make it possible for new sectors to emerge political—thrive on density.

Figure 1. High-rise, high density, New York City. Figure 2. High-rise, high density, Hong Kong.

6 ZELL/LURIE REAL ESTATE CENTER REVIEW 7 In a global economy, with uncertain Euronext, has constituted itself as a markets and changing conditions, the transterritorial European stock market. most advanced and speculative sectors Frankfurt is one of the most aggressive need concentrations of resources and tal- innovators in the design of financial mar- ent, dense environments where informa- kets themselves. tion does not simply circulate but gets pro- Even though density remains a key fea- duced. Managing and servicing the global ture in the business centers of all global operations of firms and markets takes cities, it is important to recognize that the enormous concentrations of state-of-the- need for thick, dense places does not nec- art infrastructure and buildings to house essarily mean that tall buildings are always this efficiently. profitable. There seems to be no hard evi- The geography of the global economy dence regarding profitability, since the rel- consists of both concentrated nodes— evant information is not public. Tony Figure 3. Medium-rise, high density, London. cities—and diffuse networks and electron- Travers and the co-authors of the recently ic markets that span the world. Today, a published Tall Buildings: Visions of the reduce the economic viability of very tall (measured according to people/urbanized network of about forty major and minor Future or Victims of the Past discuss the case buildings. However, there is absolutely no square mile; see “Measuring Sprawl” in global cities provide these concentrated of tall buildings in London: “Tall buildings evidence of people abandoning the highest WRER Spring 2002), even informed city nodes. The top tier includes New York bring with them certain cost implications. floors of tall buildings; it is the lower floors planners still equate horizontal develop- City, London, Tokyo, Frankfurt, and Paris. In fact, the taller the building becomes, the that have lower rents and are the hardest to ment with low density and sprawl. In fact, A second large group includes other major greater the costs of construction, servicing lease. there is no necessary link between hori- European cities as well as Chicago, Los and maintenance. Higher floors, however, zontal building and “thin,” or low-density, Angeles, and Boston. bring in higher rents—and an increased environments. Washington, D.C., for There is a considerable division of income that will soon cover the elevated THE ARCHITECTURE example, has set a limit of about ten floors functions and capabilities among these costs of building them. And while the OF DENSITY on all buildings, yet it is a very thick envi- cities—they are all a bit different in what occasional property developer may choose ronment. they offer the global economy. In very gen- to sacrifice rental potential in the name of In the last forty years, architects have Second, it is generally believed that eral terms, New York City is a major cen- aesthetic achievement, it must be assumed shown that density can be achieved in a far horizontal development can happen only ter for innovations in finance and special- that developers in general exist to make a broader range of forms than only sky- at ground level. In fact, there are multiple ized corporate services such as law and profit.” scrapers. In at least four ways, however, possibilities of creating networked envi- accounting. London, a major entrepôt for According to Travers, “while the costs public opinion lags what can be built. ronments high above the ground by financial flows from the world over, can of high-rise building construction have not First, it remains common to think that connecting the upper floors of buildings. absorb even small flows and incorporate changed much since 9/11, the disposition horizontal development is more or less Several of the proposals submitted for the them into major flows. New York and of firms and people to move into very high incompatible with density. Although met- World Trade Center rebuilding competi- London are the leading exporters of corpo- floors has.” The reluctance of tenants to ropolitan Los Angeles is the densest overall tion featured these connections. We see rate services to the world. Paris, through occupy the upper floors may further metropolitan area in the United States elementary versions of this in extreme

8 ZELL/LURIE REAL ESTATE CENTER REVIEW 9 climates. Minneapolis provides upper- plenty of examples of empty and technical capabilities, we can imagine much more easily converted to housing, floor connections between buildings in the windswept plazas (including the late verticality and its possibilities for density as while massive ones cost too much to downtown core. But this remains an World Trade Center) built in the 1980s stretching downward and creating com- adapt. According to Richard Burdett, one underexplored and underdeveloped and 1990s. But in the same era, cities such plex underground spaces for a variety of of the authors of the study, we need to option. as Frankfurt and San Francisco pioneered activities. think of buildings as “infrastructure” that Third, vertical development is usually lively public spaces at the base of sky- Perhaps most challenging is the fourth can be adapted to whatever the next phase assumed to mean “going up,” but it can scrapers. element: what happens when verticality in the economy is going to require. also mean “going down.” Underground Poor-quality architecture reinforces hits ground-level? We can have vibrant, space in New York City does not have a misunderstandings about density. But dense street-level life when there are mas- good name, associated as it is with sub- each of these four elements can be recon- sive tall buildings in our midst, but the ways. But cities as diverse as Moscow, ceived. Architectural horizontality has buildings have to be tall in a new way. Tokyo, and Montreal have made good- taken on a whole new importance at a The issue of density and vertical design quality space in underground sites, usually time when economic, cultural, and politi- has been studied by the Cities Program at linked to transportation. Underground cal networks—meant to operate horizon- the London School of Economics, which uses include retail, entertainment, com- tally rather than hierarchically—have been has produced a study now adopted as offi- mercial, and parking. recognized as crucial. Today, we can think cial policy by the British government. Finally, tall, high-density buildings of networked architecture that produces Several key findings are of interest here. have become associated with dead public horizontal spaces capable of high densities One is that there is no tight correlation space at ground-level. New York City has far above the ground. With our new between height and density. Three thirty- story buildings do the same work as one ninety-story structure; the three-building approach permits more experimenting in form, but also, according to the study, higher rates of economic return. A second finding concerns adaptivity and building bulk. Most recent commercial construc- tion is “fat” building, with giant floor plates. While useful for certain functions, such as trading floors, fat buildings may not be reusable over the long run. Office buildings often find new lives as residential buildings, as recent redevelopment has shown in Lower Manhattan and other American cities. The British study found Figure 4. Medium-rise, high density, Paris. that thin high-rise office buildings can be

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