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High Intensity Urban Order
Patrik Schumacher, London 2016
Published in: Cities to Megacities – Shaping Dense Vertical Urbanism
Proceedings of the CTBUH 2016 International Conference, Council on Tall Buildings and Urban Habitat, editors: Anthony Wood, David Malcott, Jingtang He
We live in an era of urban concentration. Density via high-rise structures remains a primary agenda. It is crucial to understand the societal forces that drive concentration: the insatiable communication requirements of Post-fordist Network Society. In contrast to prior Fordism/Modernism, urban intensification is no longer a matter of density only, but crucially a matter of mixity and communicative intensification. Current agglomeration economies are much more economies of scope and communicative interaction rather than economies of scale and logistics. This has consequences for high-rise typology. The standard typology belongs to the bygone Fordist paradigm of segregation and repetition, resisting complexity, and still driven by pure quantity. The volume is generated by extrusion: the multiplication of identical floor-plates, surrounding a core that blocks communication both across the individual floor-plate and between floor plates. As space programs differentiate with soaring internal and external communication needs, the solid central core becomes more and more an obstacle to navigation and communication. This core needs to be exploded and replaced by navigation voids that turn towers from shelves into vertical streets. This paper addresses the theme of vertical urbanism for mega-cities with a specific proposal: the mega-atrium as the typology for the mega-city.
What Drives Contemporary Urban Concentration?
Since the 1980s we are witnessing a sustained drive towards urban concentration in global hub cities. Within contemporary network society, the productivity of everybody depends on being plugged into urban professional and cultural networks that exist only in the big cities. What each of us is doing needs to be continuously recalibrated with what everybody else is doing. All further productivity gains depend on this, and it requires a new level of communicative density that is only available in the metropolis. This underlies what economists measure as ‘agglomeration economies’. In the provinces, entrepreneurs and workers are cut off and thus relatively unproductive. Since the neat division into work and leisure has disappeared and we feel the vital urge to remain connected to the network 24/7, it is as important for us to live in the city as it is inevitable for us to work in it. The driver behind contemporary urban concentration is thus the insatiable communication requirements of Post-fordist Network Society. Everything piles into the centre, the more the better. This spells a new desire and thus the architectural task for an unprecedented degree of urban intensification.
London, with its relentless growth (and yet endemic undersupply of accommodation) is a paradigmatic exemplar of the urban concentration process in global hub cities. This new urban dynamic is a fascinating challenge for architects, but more degrees of freedom are required that enable urban entrepreneurs (and their architects) to experiment, discover and create the best ways to weave this urban texture and garner potential synergies through innovative intricate programmatic juxtapositions. Only an unhampered market process can offer the freedom and the incentives required to discovery and implement the productive synergies that allow our cities to thrive. Only markets have the information processing capacity and agility to assemble a viable complex urban order for this novel societal context. This is why positive, physical Modernist urban planning had to be abandoned, and planning thereafter was confined to operating negatively, by means of restricting private actors. The result is a less regulated form of urbanisation. This mode of development is certainly better adapted to the new socioeconomic processes than the bankrupt, simplistic order of Modernist planning and urbanism. However, it produces an urban scene that is perceptually hard to digest, a paradoxical and menacing phenomenological sameness despite the rich diversity of its contents.
Postfordism’s communication density becomes physically manifest in high performance urban centres like the City of London. London is a paradigmatic exemplar of the urban concentration process in global hub cities. As more and more large iconic structures pile into the financial district, the urban landscape becomes more and more chaotic, an unintentional bricolage. The planning process is evidently failing to stem the visual chaos and unable to establish any semblance of urban order. The historical task of urban intensification is thus met only physically but not yet architecturally in terms of making density navigable, liveable and thus truly productive.
White Noise Urbanisation
While the new diversity and open-endedness of post-Fordist social phenomena is being accommodated, the unregulated agglomeration of differences has produced the global effect of white-noise sameness everywhere, without allowing for the emergence of distinct urban identities. The result is a disorienting visual chaos that might best be termed ‘garbage spill urbanisation’. Like in a garbage spill, the urban agglomeration’s diversity of ingredients is no longer perceptually decipherable. Tokyo is perhaps the most notorious (and often celebrated) example of visual urban chaos that spells both vitality and menacing disorientation. There is indeed an underlying, market-driven programmatic order, due to the market participants’ persistent hunt for synergies. However, due to an over-abundance of material construction possibilities and attendant stylistic choices, this order is rendered obscure.
This phenomenological disarticulation of the city’s organisational complexity hampers the full potential for complex social ordering because it compromises the vital communicative capacity of the built environment. Social functionality depends as much on subjective visual accessibility as it does on objective physical availability. Social cooperation requires that specifically relevant actors find each other and configure within specific communicative situations. The failure to grasp this instrumentality of the built environment’s appearance has for too long hindered architecture’s proactive pursuit of formal articulation as a key competency of the discipline. This insight motivates my explicit design research programme aiming to articulate a complex variegated urban order that allows for intuitive navigation and orientation within an information-rich built environment that makes its offerings visually accessible; that is, the design agenda of Parametricism2 and parametric urbanism.
There is no doubt that new computational ordering devices such as gradients, vector fields, and methods of associative modelling and geometric data-field transcoding allow designers to generate intricately ordered urban morphologies with distinct identities that could in principle make a much larger amount of programmatic information perceptually tractable. However, this raises the question of how this desired increase in urban order can be implemented in the face of a receding state planning apparatus.
A Market-based Multi-Author Urban Order?
One obvious way in which the vacuum left by state planning can be filled is by means of ‘private planning’, a process whereby private development corporations or consortiums unify larger development areas within a coherent, market-controlled urban business strategy. Although isolated insertions continue, there is a tendency to try to merge and integrate developable land parcels within historical centres, and also a tendency towards larger and larger privately master-planned development sites in the wider expanse of the global megacities where development is concentrated. In this sense, private planning is on the rise and thus affords opportunities for visual as much as programmatic integration. The example of London’s great estates offers an encouraging historical precedent here – of private, market-based, long-term urban asset management and planning establishing an urban order that is inclusive of a visual architectural order. However, the question remains: is the degree of order that parametric urbanism aspires to possible beyond the level of integration achievable via private planning? More generally, is an aesthetically ambitious urbanism at all possible in the face of free-market dynamism?
The market process is an evolutionary process that operates via mutation (trial and error), selection (via profit vs loss) and reproduction (via imitation of profitable solutions). It is self-correcting and self-regulating, leading to a self-organised order. We might therefore presume that the land-use and thus the programmatic dimension of the urban and architectural order is best determined by architecture’s private clients within a market process that allocates land resources to the most valued uses. In a market driven process these uses cluster - either spontaneously or according to private planning - according to criteria of complementarity facilitating social cooperation. What works together comes together. This is what I call ‘programmatic order’. However, in the absence of stylistic and methodological coherence we cannot expect the underlying programmatic order to become legible as spatio-morphological order. For this to happen we must presume a hegemonic stylistic and methodological paradigm that has does not only imposed coherence but has the versatility and ordering capacity to translate the social-programmatic order into a complex variegated spatial order. A shared paradigm offers the prospect of a legible coherence across multiple authors working for multiple clients. No controlling hand needs to be presupposed.
Parametricism can thus draw from and exploit the powerful analogy of nature’s multi-species ecology for an unplanned, multi-author urban ecology. Consider the way that various features and creatures within a natural environment coalesce to create a complex variegated order based on rules – in turn based on the complex interaction of multiple laws of nature – that establish systematic correlations between the different organic and inorganic subsystems that make up a natural landscape. The topography correlates with the path of the river; the river, together with the topography and sun orientation, differentiates the flora; and the differentiation of the flora – with the river and topography – shapes the differentiation and distribution of the fauna, which in turn impacts back on the flora and thus often also on rivers and even on the topography. While this causality is complex and not easy to unravel, correlations are being established in all directions, providing information for those who want to navigate such a landscape.
The key here is the build-up of correlations. Each new species of plant or animal proliferates according to its own rules of adaptation and survival. For instance, moss grows differentially on the terraced rock surfaces of certain shaded slopes depending on surface pattern, sun orientation, rock formation and so on. A population of a certain species of birds might then settle on these slopes. In the same way, Parametricism envisions the build-up of a densely layered urban environment via differentiated, rule-based architectural interventions that are designed via scripts that form new architectural subsystems, just like a new species settles into a natural environment. This process delivers rich yet fully correlated diversity if designed according to the heuristics of Parametricism. Each new architect/author can be uniquely creative in inventing and designing the rules/scripts of their own project, and participate in their own unique way in the build-up of a variegated, information-rich urban order. This analogy also extends to the navigation of rule-based environments: the urbanite’s intuitive orientation within a parametric urban environment functions analogous to animal cognition/navigation in a natural environment.
From Mere Density to Synergetic Intensity
Urban intensification implies more than mere density of agglomeration: It implies close cooperation between the many urban facilities that attract each other and together evolve the urban centre as integrated functioning system. This process of mutual attraction is a market process mediated by urban entrepreneurs. It is the developer’s aim (and underlying cause of success) to garner the potential synergies that reside in the selected urban site due to its location among adjacent facilities. The more freedom is granted to entrepreneurs and markets to experiment with land use allocations, density and new real estate products, the more can we presume an intricate programmatic order to emerge. (In contrast we should expect bureaucratic planning prescriptions to result in arbitrary adjacencies which do not lead to synergetic co-operations.) The theory of market-based urban order starts with this premise. On the basis of this premise the task of the individual architect must be to spatially organize and formally articulate the value-enhancing connections that are implied in the developer’s value hypothesis. The new building is to be embedded into its context in such a way that all synergetic relations are established through access relations and visual connections and become also articulate as formal affiliations via strategies such as alignment, similitude, morphing etc., so that what is programmatically similar or works together is formally assimilated and seen to belong together. The task of formal articulation is important. It enhances the communicative capacity of the built environment. Mere inter-accessibility and inter-visibility – albeit crucial – are not enough. As the urban scene grows more complex the problem of perceptual tractability and legibility arises and thus the task of phenomenological articulation. Users must grasp what belongs and works together, they must be able to cognitively decompose a complex agglomeration into relevant units of interaction, i.e. they must be able to identify the urban offerings and navigate their synergetic relations. This should be recognized in the architect’s aesthetic values guiding the formal resolution of the project.
These values shift with every aesthetic revolution, i.e. with every new major style. The formal heuristic rules and attendant aesthetic prerogatives of parametricism promote this emphasis on making connections and articulating continuities. Every space communicates with many other spaces, every subsystem is correlated with many other subsystems, the formal features of the new building resonate and affiliate with many features in the urban context. This is the ethos - one might even say the categorical imperative of parametricism: always correlate, never rest with mere adjacency. If we presume that within our complex, dynamic cities successful entrepreneurs manage to establish synergies in ever new and often unexpected ways we can no longer rely on architectural stereo-types and must instead bank on architecture’s increasing originality and open-ended adaptive versatility via its new compositional repertoires. Parametricism is unique in the way it expands architecture’s repertoire and degrees of freedom (via variable form-finding involving dynamic curvelinearity) while simultaneously increasing its ordering capacity via associative logics and agent based self-organisation. Parametricism is well prepared to handle and articulate the new entrepreneurial synergies, it can follow and make legible the entrepreneur’s transformation and post-rationalisation of found contingencies into integrated assemblages or newly minted units of interaction. Thus parametricism has the ability to build up a legible urban order leading to the emergence of a path-dependent (unpredictable but recognisable) overall urban identity with various local sub-identities. This hypothesis is premised on the hegemony of parametricsim, similar to modernism’s hegemony in 1960, whereby all architects hired by all developers would follow parametricsim’s ethos and imperative: establish correlations and maintain continuities. These continuities would then radiate through the city, in ever new creative ways. This is the hypothesis of the city conceived in analogy with a multi-species ecology.
Unleashing Internal Complexity, Mixity and Communicative Intensity
The agenda of urban intensification via synergetic mixity has radical consequences for the high-rise typology of our urban centres. The standard typology belongs to the bygone era of Fordism with its modernist emphasis on functional segregation and endless repetition, resisting variation and complexity. The standard tower is driven by pure quantity and tight packing. The volume is generated by extrusion: the multiplication of identical floor-plates, surrounding a core that blocks communication both across the individual floor-plate and between floor plates. As space programs differentiate with soaring internal and external communication needs, the solid central core becomes more and more an obstacle to navigation and communication. The prerogatives of inter-accessibility and inter-visibility between spaces demand sectional connections and visibility across floors. This core needs to be exploded and replaced by navigation voids that turn towers from shelves into vertical streets. The circulatory requirements of the tower must be radically divorced from its structural stability requirements. This technological synergy must be given up to liberate navigation from stability. Structural stability should be delivered via a skeleton - ideally an exo-skeleton that gives character and identity to the tower - rather than via a closed shaft or tube. The skeletal rather than closed tubular structure is also much more transparent and permeable. This is important to achieve visual porousness.
The variety of offerings needs to be made visible in order to become effective. Urban users should be able to browse the programmatic offering of the tower just as we browse urban spaces and streets. This is delivered by the idea of the big atrium pioneered by John Portman since the 1970s. The wider the atrium, the more floors become inter-visible. This leads to the idea of the mega-atrium that is both very wide and very tall. Such atrium might also offer bridges that cut across and bring programmes of special importance into prominent view. The atrium would also cut down and connect basement levels into the overall orientation space. In mixed used towers with different categories like retail, food & beverage, entertainment, culture, offices, and hotel functions the atrium might change shape or might be articulated into multiple interlocking atria. Navigation through the atrium should ideally happen in multiple modes: global movement via panoramic elevators, regional movement via escalators, and local movement via stairs and ramps, as well as via bridges and ramps crossing the atrium. Such bridges might also continue as bridges from tower to tower in multi-tower clusters. In addition to bridge links between towers and their atria we propose that mega-windows should open up our tower atria to vistas from outside and eventually to visual connections between towers. With the same intention of communicating across towers we are proposing outdoor terraces that link towers visually and that link back into the interior atrium of the tower. While each atrium creates a fascinating internal word – an interior urbanism – it remains important to maintain awareness and visual connection with the surrounding urban fabric.
Bridges between towers do not only operate organisationally by creating physical links but also operate in the phenomenological and semiological dimension by articulating what belongs together and by signalling where high connectivity zones like retail areas are located. The use of curvature allows designers to maintain legibility in the face of increasing complexity. While providing flexibility in terms of adaptive swelling and swerving, curves also facilitate legibility by describing convex volumes, concave voids and continuous trajectories in visually more robust ways than straight lines with corners and kinks could. The issue of cognitive tractability and the visual decomposition of complex scenes become increasingly important and can be studied with respect to the psychology of perception, in particular in terms of Gestalt-psychology2. The Gestalt grouping principles of closure and smooth continuation privilege curves over straight lines with corners. Every corner represents a potential point of visual disintegration, leading to the cognitive break-down of figures that are intended to signify relevant units of interaction: the objects of interest lose recognisability and the project as a whole is in danger to fall apart. That is why we prefer to compose with curves, especially when it comes to complex compositions. This bias towards dynamically curved geometries also extends into the realm of urban design. Here too curvature helps to articulate unity and continuity, while affording variability in response to both contextual and programmatic contingencies. An urban geometry based on curves can better navigate topography, river edges, and other irregular contextual conditions. A soft grid offers plot and block size variability, i.e. economies of scope, which is a better default position than a rigid grid that can only offer a one-size-fits-all set of repetitive plots. Swarms, height gradients and soft silhouettes facilitate the visual articulation of urban districts, features, identities. The convergence of the discipline towards these insights would go a long way towards regaining a sense of urban order in the face of society’s restless dynamism of high density urbanisation and permanent innovation.
Fig.1 &2 ZHA, Soho Galary, Beijing: This cluster of four towers is connected via bridges. Bridges dominate at the upper edge of the retail zone and are thus signalling the transition between retail and offices. Retail areas are also connected on both ground and lower ground. Each tower encloses an atrium that connects both upwards to the top retail floor and downwards into the lower ground. Escalators pull into the atrium for easy navigation. Each atrium is covered by a glass dome. The void continues above as an open light-well or courtyard for the offices.
Fig.3&4 ZHA, Jockey Club Innovation Tower, Hong Kong: This tower accommodates the Design School of Hong Kong Polytechnic and thus mandates the maximization of internal communication. The tower is composed of two fused slabs and offers three internal atria, each lit with daylight from above. All class rooms have windows to the outside as well as glass walls into one of the atria. The tower lands on a complex, multi-level terrain and allows an outdoor path to move through its base. Several terraces offer break out areas and visual connections back into the campus.
Fig.5&6 ZHA, Dominion Tower, Moscow: This tower is a multi-tenant office building. The structure is made from perforated walls placed so that floor plates can shift and cantilever affording column-free facades opening the offices into the urban context. The offices also have glass walls on the inside and are thus equally connected into the central navigation void and to each other. Communicative intensity is facilitated and signalled via the stair bridges that cross the day-lit atrium. This heightened visibility of the circulation elements that invite to linger – seening and being seen - is conceived as hub for cross company informal communication. A cool building certain to attract a cluster of mutually relevant cool companies.
Fig.7&8 ZHA, Urban master-plan for Beijing CBD: Our proposal for Beijing CBD comprises a whole group of towers of various heights, all equipped with a central navigation void instead of the standard central core. Balconies allow for visual participation in the central experience and panoramic elevators facilitate the fast browsing of the space. The largest tower shown here is composed as a merged cluster of four towers. One of the four towers sponsors a mega window instead of a bank of panoramic elevators, affording a dramatic visual connection into the urban fabric.
Fig.9&10 ZHA, Soho Li Ze Tower, Beijing: This tower is addressing the usual SoHo – Small Home Office – product of small office units and shared office spaces in a tall tower typology. To afford the desired communicative intensity that comes with clusters of start-up companies we decided to open up the tower all the way and create China’s tallest atrium, 200 meter high. Retail and food & beverage facilities are located at the bottom and around in a sunken courtyard, also reached by the atrium. The atrium and indeed to whole tower is opened up via two gigantic vertical windows that slightly spiral around the gently swelling tower form. Four high level bridges that cross these windows give additional connectivity and spectacular vistas.
Fig.11&12 ZHA, Taikang Regional Headquarters, Wuhan: Our most ambitions mega-atrium so far. The top lit atrium is cut open by large paraboloid arches at the lower levels and traversed tangentially by multiple bridges in the upper third. The floor plates are swelling close to the bridge connections as if gradually pushing the bridges forward. Panoramic elevators pull up at the edges of the atrium, at times pulling behind the projecting floor slabs. Total communication: Nearly every space is visible to every other space.
2 For a theoretical elaboration of architecture’s phenomenological project on the basis of Gestalt-psychology see: Schumacher, Patrik, The Autopoiesis of Architecture, Vol.2 A New Agenda for Architecture,
Publisher: John Wiley & Sons Ltd., London 2012, in particular: section 6.7 The Phenomenological Dimension of Architectural Articulation
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