Agree -- or Disagree -- with Prince on Tall Towers in Old Cities?

HRH The Prince of Wales recently discussed his opinions of tall buildings in London. He was quoted as saying London had a "pockmarked" skyline, because its modern glass skyscrapers are not clustered together. I think there is a lot of truth to that. First time visitors may be surprised to see that: a) there are skyscrapers in such an old city and b) that they are relatively few and far between. Central London has a bit of an identity crisis at the moment.

Paris, on the other hand, is a good example of an old city that has preserved old urbanism in its core. Modern blemishes like Montparnasse and other high rises in the 13th and 15th arrondissements, don't add value to Paris' skyline, but at least they are on the fringe and don't interfere with the central city. True, it would be better if these eyesores were non-existent, but like elevated freeways in cities - you'd rather have them away from the core.

Paris has successfully made La Defense (an inner suburb) its Central Business District, without having to do what London has done. Although the modern skyscrapers of La Defense starkly contrast the elegant architecture of Paris, their geography creates a sense of two distinct cities, one old and one new. (They are different municipalities.) Turns out the Prince has had some relatively positive things to say about La Defense too.

London may be hard pressed to replicate La Defense, but at this point maybe it will have to embrace the modern skyscraper to undo its "pockmarked" image.


The Prince wants your views on towers

The Prince's Foundation is seeking comments on this issue. Here's the link and what the foundation's site has to say about this debate.

HRH The Prince of Wales's speech at our New Buildings in Old Places with the Prince's Regeneration Trust has triggered an avalanche of interest. While much of the focus has been on the issue of tall buildings, people have also commented on the challenges of meeting the demand for housing in an ancient land. Because of the outpouring of support -- and challenge -- we have decided to open up an interactive part of our web site, so that people could comment and debate the issues.

Some of the issues that we expect to generate lively debate are the following:

1. Should tall buildings be concentrated in urban quarters -- like Canary Wharf -- to create a new skyline? Or should they be permitted where a local authority or a developer wishes to make an architectural statement or statement of aspiration?

2. Are world heritage areas adequately protected from new construction? How can new construction add to the visitor experience?

3. Density is often cited as the reason for building taller. Are residential towers the answer to the housing crisis? Or should we increase density by building terraces with small gardens and mid rise mansion blacks with private courtyards?

4. What's more important: the ability of tall buildings to make an artistic statement, or the need for buildings to fit into a walkable mixed use neighbourhood?

5. Significant architectural monuments used to be reserved for public buildings and cultural destinations on key urban sites, yet many proposals for iconic buildings are coming for speculative office buildings and residential towers on opportunistic sites. Is this just the way it is in the contemporary world, or should planners take a stronger hand?

Towers of London

Towers of London
The question posed is perhaps more sweeping than the urban design problem apparent at first glance. The question is really about patterns of development and context sensitivity. At issue are transportation, historic preservation, economic development, and neighborhood development.

Intensity, Iconography and the Circus Tent
Villages grew up around marketplaces, churches, and other important places. These centers became the icons around which our neighborhoods and access patterns converge. A clustering of tall buildings and intensity of activity in general arises from agglomeration economies and access to goods and services at these centers. The most accessible location is on average going to be the most valuable place to be and people will crowd that area. As land becomes more valuable relative to the cost of building, buildings go higher. Technology and cheap energy has enabled us to go up, such that a good measure of this intensity of activity in many places is the height of building. It is important to distinguish between residential concentration (density) and activity concentration (intensity). Commerce predominates in the intensecenter and residences gravitate around it, height and hubbub being more appealing to commerce than homes. This height has the additional benefit of wayfinding and establishing the identity of the village/neighborhood. The icons relate to our activities not our dwellings. If we de-intensify areas or dissociate the icons from the areas of intense activity, we induce more transportation and sprawl. Too much intensity also presents difficulties: blocking sunlight or views, limits to access or as Yogi Berra said, “nobody goes there any more, it’s too crowded”. The drive then starts another place elsewhere, creating a circus tent-like pattern with a central peak surrounded by smaller peaks, each creeping upward supplied and sustained by tethers to the surroundings. If any peak gets too tall relatively or the tethers cannot hold, the tent collapses or must remain smaller.

Science of Multiple Forces
Perroux’s Growth Pole and Christaller’s Central Place, theories about the placement and structure of cities, are the competing forces of growth and nucleation in nature, respectively. There is a “potential” that exerts a force on a system: temperature in the case of solidification, chemical in the case of precipitation, and economic/resource access in the case of human activity. When the potential, the difference between need and satisfaction of that need, gets high, ice crystals, precipitates and communities nucleate and grow – either in a dispersed pattern of small crystals (nucleation) or in one big crystal (growth) depending on the play of forces. The size pattern can be manipulated by scientists with seeding (e.g. minimizing spangle) with addition of small particles or prior growth patterns to keep crystals small or they can cultivate huge single crystals through carefully controlled conditions (e.g. silicon boules used to make chips). Left to natural forces, usually a mix appears. Over time, other forces come into play including coalescence and Ostwald Ripening, making one big crystal from several. All crystals have a center and an edge, the center usually being the thickest part. The potential determines how thick or how many crystals. The fuel is access to the materials for growth: energy or components.

City Nucleation and Growth
For cities, history adds nucleation sites and vestiges of old drive forces. New forces can arise, but also may be ephemeral – if adapted to, then growth patterns will largely disappear (Erie Canal towns, etc.). To enact a desirable pattern, strategic energy must be put into the system to get the desired results, preserving the system or effecting a new desired system. What system and what needs are served by the structure? How much strategic energy is needed to effect the desired outcome? If the strength of existing forces is too strong, efforts will come to naught. Address the needs better in a more sustainable way and the reward is a damasked blade, beautiful spangle or ice art – beautiful and functional. You can nucleate multiple centers with smaller intensity centers often seeded with historic villages or allow a big crystal to grow as in the US. Or, you can have a controlled mix with small villages (Etoile, Les Halles), and allow a big crystal to grow on the edge (La Defense). Natural forces will continue to play and may grow La Defense at the expense of Paris or the fuel may literally dry up and smaller villages may be more sustainable.

London and Its Structure
Prague with its series of quarters that each have character and a center with a small increase in intensity is lovely but not as prosperous as London. Paris’ center is nucleated on monuments to its past glory, but presents a large problem for business which has created awful commercial sprawl on its periphery. The Eiffel Tower was not intended to be permanent, nor was it embraced at first. Vance claims that the great fire transformed London from a medieval labyrinth to a wide grid of streets and system of conveyance that enabled it to become a mecca of business, precisely because it catered to commerce rather than monuments. The building boom of London results from the “potential” being too great – but is that business or residential “potential” or both? Indeed it is a dialog, but can the goods and services get to and from these areas? Is the intensity located at the center of the districts or rather they are randomly spread? Do they reinforce the purpose of and satisfy the needs of the districts? Do they have the proper iconography or are they about opportunism at the expense of the district? This may be London’s problem, rather than whether all towers need to be out of town. St. Paul’s Cathedral united London during the Blitz. It is doubtful that yet another randomly placed ice cube tray will do the same, but revitalizing neighborhoods need nucleation sites and space for centralized activities. How important is tourism as an industry? Can the building(s) or pattern(s) stay viable with high energy costs? Should London be like other places? Perhaps there are more questions than answers, but there may be more than one good answer. London should decide what it wants to be in the future and cater strongly to it; then, form will probably follow function.

An Answer or What It Might Look Like

London is not Paris and has traditionally been a bumpy quilt of woven streets and neighborhoods rather than a plateau dotted with monument spires. It has catered to commerce particularly within the square mile. Traditional structures that are the current icons are not “intense” enough to accommodate the “potential” or latent demand and it would be unsustainable to banish commerce to sprawl outside London. The icons may still be located in properly distributed walkable districts around London. I would focus on the icons that co-align with these centers. Wrap them in a square-type structure of more intense buildings that face and focus on the icon with highly visible and transport-capable pathways leading to them. The intensity of the surrounding square enhances icon status to the traditional structures. The boulevards that lead to them carry large amounts of multimodal traffic to these centers and add visibility to the icons themselves, while allowing commerce to thrive IN London. The centers need to be networked to facilitate district to district movement and connection. This might put the tall buildings where they belong and not where they do not. Garden mid-rise mansion blocks could fill the remaining quarters of the districts, so that people who want to live in London may be able to afford to do so and sustain the district centers.

In the end, blades rust, ice melts and cities either reinvent themselves or nucleate elsewhere. If left to chance, raising tents leads to collapse and redoing, at great cost. If planned, this natural progression can be avoided and lead to structures that will last.

Andrew L. Gast-Bray, Ph.D., AICP
Adjunct Professor of Planning, Ball State University
Storrow Kinsella and Associates
Indianapolis, IN 46202

