The Guru Is In
Historic verticality
By David A. Smith
4 min read
When first I saw a gleaming new tower sprouting within, and above, the five-story brick crust that was all that remained of a decrepit century-old block whose guts had been scoured out and trundled away, I thought the surface preservation both incongruous and a waste of money. In the decades since then, I’ve changed my mind even as the world’s historic cities have changed around us.
Cities have changed their structure more over the last hundred years than in all the human existence that went before. Electricity led to the elevator, which when coupled with steel brought the skyscraper, which brought zoning. All of them together created a vertical boom (epitomized by the Empire State Building) that spread around the world and shows no signs of stopping.
The changes in the urban fabric over the last hundred years are nothing short of astonishing. Once the city freed itself from the tyranny of staircase-based verticality, the urban value proposition likewise upended. Where once the city was fortress, marketplace, and factory, in short order it became a mind-hive that produced immensely valuable intangible goods – education, innovation, and finance. Add to that instantaneous communication of ever-widening circles – telegraph, telephone, internet, and now the globally networked broadband – and it becomes apparent that the most valuable economic asset in any global city is its people.
That repricing of assets has transformed our cities. To aggregate the brainpower needed to spark wealth creation, cities need large volumes of people in very close proximity to each other, and for that there is absolutely no alternative to stacking us into high-rises. Instead of expanding out, information cities expand up.
Remaking a horizontal city for verticality means a revolutionary change in building structures. Inescapable laws of physics and engineering mean that like creatures, buildings have allometric scaling: as they get taller, they must take the load off the external walls and place it on an interior load-bearing core, and because people like natural light, the ideal curtain wall is glass. Hence all the façade brick and stone that our great-grandparents’ architects deployed, not for aesthetics, but for strength that became structurally obsolescent. In fact, the ability to go up and up, to create built environment in the sky, has rendered the downtown historic building vertically obsolescent – in purely economic terms worth more gone than retained.
Nor is that all. Those same inconvenient truths of physics require taller buildings to have a proportionately larger footprint, so the urban plat divisions laid out by our forebears are too small and the land has to be assembled – which means invoking eminent domain, and that entails engaging local government, custodian of this urban power. That power to block verticality by withholding eminent domain gave first local, then state or national government, the leverage to demand that the façade be preserved.
Governments around the world have enacted historic preservation laws. What makes America’s system different and better is our use of calibrated tax incentives – principally the Historic Tax Credit – to counterbalance the ‘preservation surcharge’ – the additional development cost required to maintain a physically dysfunctional, but stylistically pleasing, surface around the building’s base.
Subsidizing historic preservation is economically farsighted for municipalities. Between real estate taxes and business expansion and economic activity, the municipality is the ‘economic silent partner’ of every urban private property owner, claiming 20-40% of the property’s true economic value. Thus private development expenditure boosts the public coffers by much more than the tax expenditure of the Historic Tax Credit.
In addition to that urban-economics case for the Historic Tax Credit, when we preserve an older pre-elevator façade as an outdoor wainscoting, a magical serendipity occurs: we create the walkable post-automotive vertical 21st century city. When we walk, our tactile experience is shaped by only those first five stories, because they are the details close at hand for us to observe. Conversely, the skyscraper’s surfaces would be antiseptic, anonymous, and distancing if viewed up close, but when seen only at height they might be abstract clouds, for indeed their tinted-glass curtain walls make them appear nothing more than changing patterns of light and shadow.
The next time you take an elevator above the 40th floor of a downtown office building, gaze out and down. Spread below you will be a hundred or more years of urban evolution, verticality, and you’ll see a century and a half’s verticality displayed below you: Five-story buildings from the 1890’s, twenty-story from the 1930’s, forty-story from the 1980’s, and today’s new spires rising in their midst to accommodate the new workers drawn to the city both by the jobs in the sky and by the tradition at ground level.
Historic and vertical: the 21st century city.
