Widely acclaimed as a global city, New York’s eclectic mix of boroughs and neighbourhoods
gives it a rich and diverse identity that is envied the world over.
Shaped by nearly two centuries of economic cycles and the architectural and urban planning
trends that accompany them, the city that never sleeps is also continually evolving.
But one particularly notable development in recent times is the rise of a Manhattan neighbourhood
that caters for the super-rich.
With breath-taking views, luxurious interiors, endless amenities and eye-watering price tags,
this new wave of properties are strictly for those with a 10-figure bank balance.
But how did this area come to be?
What sparked its growth in this particular district?
How were planning controls addressed, and how did engineers make the development of such
small scraps of land commercially viable?
This is the story behind New York’s “Billionaire’s Row”.
With its extreme popularity and highly restrictive geographic context, Manhattan Island is today
one of the most densely populated areas on Earth.
For decades developers have competed for space here, balancing their quests for return on
investment with the requirements of the city’s planners and respect for the differing identities
between the island’s many neighbourhoods.
Those distinct areas shape the city we now experience
from the high-rise financial
centres around Lower Manhattan and Midtown
to the villages of Chelsea, Greenwich and Soho
and the exclusive addresses of the Upper East Side.
While planning controls have helped to create clear identities between these different neighbourhoods,
they have also made any significant redevelopment of sites in established residential zones
remarkably difficult.
With Manhattan’s popularity ever increasing and rising demand for luxury residences,
developers have begun to venture into commercial areas in search of suitable sites.
Situated to the immediate south-west of Central Park, the Midtown streets between Park Avenue
and Columbus Circle have long had an air of prestige.
Home to the iconic Plaza Hotel, the Russian Tea Room,
Carnegie Hall and intersected by the desirable Fifth Avenue
the district is naturally appealing for high-end residential developers.
In the last decade, several significant schemes have emerged in this zone, and in particular
along 57th Street, leading the area to become dubbed “Billionaire’s Row”.
The completion of One57 in 2014 was followed by the opening of 432 Park Avenue in 2016
and the development of 53 West 53rd Street, 111 West 57th Street and Central Park Tower thereafter.
These schemes offer extreme luxury against the backdrop of unique Central Park views,
addresses in some of the city’s most desirable streets and close proximity to high-end retail outlets.
There is also the added benefit of avoiding Manhattan’s co-operative arrangements, where
buyers typically purchase shares in the corporation that owns a property in exchange for the exclusive
use of one of its units.
These arrangements demand the disclosure of financial information
that doesn’t always appeal to the super-rich.
With apartment sale prices starting in the tens of millions and extending well into hundreds
of millions, developers have seen returns of several billion USD on these schemes to date.
But building here is not easy.
Suffering from extreme over-development, carefully governed
by planning laws and with only very small sites available, developers and their project
teams have been forced to innovate.
Commercially, developers need to maximise floor area in order to recover the costs of
purchasing and developing their sites.
This often leads them to plan structures that go right up to site boundaries.
Concurrently, all schemes must adhere to New York’s strict Floor Area Ratio (FAR) planning
legislation that controls the height of a structure, relative to the size of its site.
To overcome this potential obstacle, developers purchase air rights from neighbouring properties
and effectively stack them onto their sites.
For city planners, this approach protects
against the over-development of surrounding properties in the future, while developers
and those living within their structures are assured light and clear views out.
These arrangements have the added benefit of generating capital for those selling their
rights, enabling them to progress with smaller scale construction projects on their own land.
53 West 53rd Street is perhaps the purest demonstration of this concept to date.
Here, the existing Museum of Modern Art (MOMA) sold an area of land adjacent to their main building
together with the air rights above part of their estate.
This enabled the construction of the Jean Nouvel designed 53W53 tower
while generating funds to re-develop the museum itself.
The link between the two structures on the site has thankfully been retained in Nouvel’s
notably artistic design – that responds to numerous zoning and setback constraints
– and in benefactor memberships at the museum for those purchasing residences within the tower.
With such small sites in their possession, a strong desire to build high and maximise
floor area, and the legal constraints of doing so removed, developers have turned to their
project teams to solve the challenge of building super-slender towers
structures that are defined as having a width-to-height ratio greater than 1:7.
By moving away from steel and embracing high-strength reinforced concrete, engineers have been able
to increase design flexibility and the overall strength of their structures.
With high-strength concrete cores housing their vertical access and service routes,
super slender towers move much of their remaining structure to the perimeter of the floor plate,
negating the need for columns and maximising functionality within residences.
In the case of 53W53 and the impressive 432 Park Avenue, this perimeter concrete structure
has been stunningly incorporated into the overall aesthetic of the external façade.
But while high-strength reinforced concrete enabled these super-slender towers to rise,
further engineering was required to ensure their stability at such extreme heights.
432 Park Avenue – with a width-to-height ratio of 1:15 – features double floor cut-outs
at 12 storey intervals throughout its height, allowing powerful wind forces to pass through,
as well as around its extremely thin structure.
This prevents areas of low pressure being created on one side of the structure as air
currents move around it.
If unmitigated, these areas could create repetitive, rhythmic suction
forces that would cause the tower to sway towards its upper levels.
We have demonstrated the effect of 432 Park Avenue’s design in a simulation developed
using SimScale’s software.
With more than 150,000 users worldwide, SimScale is an easy-to-use cloud-based engineering
simulation platform that enables everyone to create powerful, high-fidelity simulations in a web browser.
The platform can be tried for free through the Community account, which
gives access to thousands of public simulations to promote knowledge sharing and to crowdsource advice.
432 Park Avenue’s open floors are combined with the use of tuned mass dampers; immensely
heavy instruments suspended in voids at the top of the structure that helps to counteract
swaying motions where they begin to occur.
The 472 metre Central Park Tower is set to become the tallest structure on billionaire’s
row, and the second highest tower in the United States when it completes in 2020.
This development combines an irregular profile with numerous setbacks to vary its façade
across its height, disrupting wind currents and preventing the formation of coherent vortices
and dominant wind loads that can result in swaying.
We have again demonstrated the impact of this approach with a SimScale animation.
Finally, with a width to height ratio of 1:24, the breathtakingly narrow and exquisitely
detailed 111 West 57th Street steadily tapers throughout its 435-metre height, breaking
up the façade uniformity that can lead to vortex shedding.
The result of these impressive engineering
developments is not just the emergence and continued rise of New York’s billionaire’s
row, but the birth of a broader super-slender skyscraper phenomenon that is starting to
influence other markets around the world.
The origin of these structures can be traced directly from New York City and their existence
is unique to this specific time in our world’s architectural history.
A product of New York’s own zoning restrictions, near unrivalled appeal, insatiable developers
and engineering ingenuity – billionaire’s row has become the latest distinct neighbourhood
in the rich tapestry of this thriving city.
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