When it first opened in 1913, the 241 metre Woolworth Building in New York City was the
tallest skyscraper in the world.
Providing 57 storeys of commercial office space within its neo-gothic inspired design,
the building was seen as a monument to capitalism and quickly became dubbed the “Cathedral of Commerce”.
Though it lost the title of the world's tallest tower in 1930, the Woolworth Building remained
an iconic symbol of New York throughout the 20th Century
gaining national landmark status in 1966.
However, as the 21st Century dawned and commercial office environments evolved, the tower’s
appeal became limited by its own design.
In response, developers looked for ways to reinvent
this iconic structure, retaining its heritage whilst making it viable in a new age.
When skyscrapers first rose to prominence, they were widely seen as symbols of corporate
power with executive management occupying the uppermost floors in a literal statement
of hierarchy that continued for much of the 20th Century.
But in the early 2000s, corporations began to move away from this vertical segregation
of departments and instead embraced more open layouts where employees could interact and
engage with their teams.
While the original design of the Woolworth Building was revolutionary for its time, its narrower
upper floors were not able to meet the demands of modern day commercial tenants seeking these
new, open plan layouts.
In 2012, as the world recovered from the Global Financial Crisis of 2008
Alchemy Properties purchased the top 30 storeys of the Woolworth Building
with plans to convert them into luxury residential apartments
a commodity that was becoming highly sought after in Manhattan.
Consisting of 33 units – including a five storey “Castle in the Sky” penthouse
worth USD $110 million –
the Woolworth Residences were set to become the most expensive in the
Downtown area
While numerous high-rise residential projects were under development across the city – primarily
in the Midtown area that would later become known as “Billionaire’s Row”
the Woolworth Building stood out for its historic status and intricate neo-Gothic architecture
that couldn’t be replicated elsewhere.
However, the unique structure presented the development team with unique challenges that
other new build schemes were able to avoid.
The highly built-up surroundings and ornate design of the Woolworth Building meant that
erecting a crane adjacent to the tower or on its roof was simply not possible.
Concurrently, the lower 28 levels of the building – occupied by commercial office tenants
were to remain in use throughout the conversion works on the residences.
To overcome these challenges, the project team had to ensure that all materials and
equipment specified could fit within the internal lift shafts of the tower, before installation
at their intended floor.
With the Woolworth Residences occupying the upper levels of a commercial building, the
need to separate residents from office tenants was a primary concern for developers.
Before works to create the apartments could commence, suitable access had to be secured.
Whilst a dedicated new entrance lobby off Park Place was one step, transporting residents
upwards, proved considerably more complex.
The highest office floor on level 28 of the tower was only accessible by three elevators,
all of which were housed within shafts that extended up to the 49th Floor.
These needed to be moved to create dedicated access for the residences and separate access
for the offices, avoiding the need for elevator cars to be shared between office tenants and residents.
However, with the commercial areas of the building remaining occupied during renovation
works on the upper levels, only one elevator shaft could be taken out of service at any
one time.
As such, all work to move the elevators and their associated mechanical plant had
to be undertaken out of hours when the offices were not occupied.
As early elevator systems were much slower and smaller than their modern-day equivalents,
many older skyscrapers typically have an oversupply of elevator shafts, as compared to new structures.
Following numerous elevator upgrades throughout its life, the Woolworth Building had a number
of vacant shafts.
However, the narrow dimensions of these shafts and their location on the tower’s floor
plate did not work efficiently with the proposed residential layout of the building.
To overcome this, a 4.9-metre-wide disused boiler flue – which ran the entire height
of the building – was repurposed as the residential elevator shaft, allowing for larger
cars and access from the basement car park to the highest floor.
Works to remove the 13mm thick steel flue were carried out by a worker being lowered
into the duct and burning away pieces of steel from within, before lowering those pieces
down through the shaft.
In order to accommodate the new, higher speed elevators for the residences, deeper elevator
pits were required to allow for overruns in the shafts.
To construct these
4.9-metre deep holes were excavated in the building’s basement, extending 2.4 metres below the waterline.
To avoid soil collapse and water quickly filling the pits during excavation, grout was first
injected into the soil to stabilise it. Once complete the pits were waterproofed and lined
with cement to prevent leaks.
With its conversion from commercial to residential use, a number of additional services were
required on the upper floors of the Woolworth Building, independent from those for the office units.
Making use of the disused elevator shafts, engineers were able to bring all services
up from street level to the 29th floor, bypassing the commercial levels before branching off
to each residence.
To provide sufficient air intake and exhaust for the tower, the four decorative tourelles
that surround its summit were adapted to house mechanical shafts which could service the
upper floors.
Crowning the Woolworth Residences is the aptly named Pinnacle Penthouse.
Spanning the five highest floors of the tower this “Castle in the Sky” is unlike any
other New York apartment.
With three bedrooms, five bathrooms, a private elevator, library, media room and private
observation deck across 9,710 square feet of space
the penthouse was marketed at USD $110 million
more than double the previous record for the most expensive downtown residence.
To create this luxurious space and meet New York’s natural light and air requirements,
Alchemy needed to secure permission from the Landmarks Preservation Committee to expand
existing windows and add six additional penetrations.
These adaptations – along with the removal of half of the 54th floor to create a double
height entertainment space known as “the Great Room” and additional floor penetrations
to accommodate the private elevator – meant that the summit of the tower required extensive
structural support to continue resisting lateral loads.
In response, engineers introduced bracing around all new openings while the entire 54th
and 55th storeys were strengthened with additional bracing around their perimeter.
As our living habits, desires and building regulations continue to evolve, it is tempting
to overcome challenging issues with outdated building stock simply by demolishing such
structures.
But with growing respect for our built heritage and increasing awareness of adaptive reuse
for large structures, the Woolworth Building stands as a prime example of how history can
not only be retained but brought forward into a new age.
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