A clear vision

The versatility of glass made it the right choice for SOM to create curved facades with maximum transparency, in a complex mixed-use development on one of Manhattan’s last undeveloped sites. Roseanne Field reports

Manhattan’s West Side Yard, a rail yard located on the ‘Far West Side’ of the island, had been the subject of various speculative development discussions since the 1950s. A portion of the site was bought by development company Brookfield Properties in the 1980s, who gradually acquired the rest of the site over subsequent years, covering an area between Ninth and Tenth Avenues, and West 31st and West 33rd Streets.

Despite the site’s clear potential, it wasn’t until 2005 when New York’s City Council approved a ‘rezoning’ – changing the ‘use’ of the land and thereby what restrictions it falls under –– that developing on it became a real possibility. A plan was therefore submitted by Brookfield for a mixed use scheme which would work within the site’s designated ‘air rights,’ creating a ‘neighbourhood’ here, on what was “one of the most underdeveloped sites remaining in Manhattan.”

The developer had a good relationship with the masterplan’s architects Skidmore, Owings & Merrill (SOM) from previous projects, and the practice has “a very long history and expertise in designing tall buildings and planning new neighbourhoods,” explains SOM principal Julia Murphy. She adds: “The project was a perfect fit for us”, detailing how it’s enabled them to rethink several consecutive blocks of the city. It encompasses a handful of new buildings around a plaza that will connect to the landscaped route known as the High Line via a new elevated pedestrian link
in 2023.

The practice knew from the outset that the project wasn’t going to be straightforward. “It was always going to be very complex, given its scale, the lack of buildable land, and the active railroad tracks underneath,” Murphy explains. “The vision was to create a vibrant new place offering everything from workspaces to hospitality and residences, with vast public space and retail on the ground to bring people into the site.”

By 2008 the practice had completed an early iteration of the masterplan, but the majority of the development stopped when the financial crisis hit. Construction of the pedestrian platform over the railroad tracks continued however, before SOM picked the masterplan design back up again in 2010.

The $5bn development occupies seven million square feet of space and comprises six buildings including One and Two Manhattan West, twin glazed towers both housing offices and 303 metres and 67 stories/285 metres and 69 stories respectively). There’s also the Pendry, a 164-room hotel; The Eugene, an 844-unit residential tower; and Five Manhattan West and The Lofts, two former industrial buildings repurposed as offices. As well as the masterplan, SOM designed three of the buildings, and engineered four of them. The buildings are located around a central plaza lined with 225,000 ft² of retail space.

Creating an overall vision for the site was the first hurdle to overcome, explains SOM principal Kim Van Holsbeke. “The first challenge was creating a holistic vision for a new neighbourhood where none really existed before,” he says. “The area was mostly empty parking lots, approach roads to the Lincoln Tunnel, and some isolated industrial buildings, all in the midst of railroad infrastructure. We had to envision what its new identity would be.” Not only is the development crucial for the revitalisation of the Far West Side, it’s described as a “gateway” by SOM, connecting the district to Hudson Yards to the west and Penn Station to the east.

Structural considerations

The second major challenge was to solve the complex engineering challenges that came with building over active railroad tracks. This wouldn’t have been possible, says Van Holsbeke, without the firms’ collective experience, it being one of the most complex projects undertaken in New York City in recent memory.” The practice’s designers, engineers, and planners had to collaborate closely to come up with the best solution for the site.

This solution had to allow the buildings and public space to exist – and be constructed – over the live railroad tracks without disrupting their operation. They designed a 2.6 acre building platform to sit over the tracks, and planned various construction phases. Van Holsbeke illustrates the tolerances they were working within: “One Manhattan West, for example, had only about 130 feet between the northernmost track and 33rd Street – an office tower generally requires about 150 feet to have appropriate lease spans, so we had to design the building on a foundation that was considerably smaller than its footprint.” The building’s central core was anchored on the city’s bedrock, but perimeter columns on the south side couldn’t be, so the building was designed with the perimeter columns on all four sides sloping down into the central core above the lobby. This consequently allowed for a column-free lobby which has been clad in vein-cut travertine marble.

At Two Manhattan West, only one half of the central core could reach solid ground, so SOM designed two ‘mega-columns’ at the perimeter, inserted into spaces between the train tracks to create what the architects call a “table top” supporting the tower above.

Invisible enclosures

With a “vast open lobby space” being created for both towers, glass enables a column-free perimeter at One Manhattan West to be an “almost invisible enclosure that blurs the line between the lobby and the plaza,” explains Van Holsbeke. The perimeter columns of Two Manhattan West are minimal, spaced 60 feet apart, “creating large window portals that are filled in with a glass cable wall system,” he says. “This system itself creates a strong visual connectivity between the indoor lobby and surrounding public space.”

The overall aim with the two towers was to “create an abstract composition, with two volumes in the New York City skyline that create a dynamic relation with each other and their surroundings,” Van Holsbeke explains. Each tower features one curved elevation, overlooking bustling parts of the island – One Manhattan West’s facing Penn Station to the east, and Two facing Midtown traffic heading south. “Together, the two buildings form a gateway to Midtown West and into the public space of the Manhattan West development,” says Van Holsbeke.

Glass’ physical characteristics made it the right material for creating these forms, explains Van Holsbeke: “To create these monolithic, sculptural buildings, with a very tight skin and that softly curved massing, glass has the bendability that most materials do not have,” he says. “It also helped us create these very transparent, triple-height lobbies that visually seem to dissolve at ground level, so you can see into the buildings and from one part of the public space to another. It offers a permeable connection to the central plaza.”

SOM principal Christoph Timm reaffirms this, saying glass has a versatility other materials don’t – making it the perfect choice for achieving the sculptural quality they were after. “Glass was the only enclosure material that could make this possible,” he says. “The vision and spandrel zones on the facade have few differences in appearance.” This also has the added benefit of allowing plenty of natural daylight and maximising views for the users of the buildings.

Glass also formed a key feature of the design of the adjacent Pendry hotel, where it has been used alongside granite to form an undulating facade which, says Van Holsbeke, gives the building a distinct identity and “subtly indicates the building’s role.” The “repeating, sinuous character” helps it stand out, adds Timm.

The designers’ thought process behind this facade was a contemporary take on the bay window – a “perfect” element for a boutique hotel in Manhattan, says Timm. “It allows the interior spaces to visually connect with the surroundings – such as the Empire State Building – to help guests feel the essence of New York, while also bringing in more natural light.” The curved floor to ceiling windows in each room give hotel guests views they wouldn’t have had with a flatter facade, as well as giving the practice a chance to create floorplates that are a little different from the norm. Externally, granite spandrels balance the glazing and “emphasise the curves of the exterior,” Timm adds.

Although it appears as though the glass facade curves continuously, this is something of an illusion, as “strategic geometric design” meant only 22% of the curtain wall panels required bending on the hotel’s facade. “To further reduce unnecessary complexity and enable the use of a low-environmental impact bending process, just three radii were utilised to generate the curves of the bent panels,” Timm explains. To give the building a “unified, monolithic expression” – as well as provide environmental benefits – the practice used a tinted outer glass substrate, “minimising the visual delta between the convex and concave surfaces,” Timm says.

Working with such high volumes of glass meant potential overheating, cooling, and acoustics were all issues to be considered. A coating was used on the glass to control heat loss and gain, though the practice faced the added challenge of ensuring this was bendable for the Pendry and the curved elements of One and Two Manhattan West. The acoustic transmittance of the glass for the Pendry was also thoroughly tested before they settled on the final curtain wall design. The tinted glass substrate used on the hotel also assists with minimising overheating, and subtle flat, operable vents were installed. “They don’t distract from the facade’s beauty,” assures Timm.

It was also decided from early on in the project that One and Two Manhattan West would target LEED Gold certification, which Van Holsbeke describes as an “aggressive goal. We had to thoughtfully design and plan the enclosure, systems, materials, and construction,” he says.

The project as a whole was “planned holistically”, Van Holsbeke continues. “We were taking essentially a brownfield site and adding density and extensive landscaping. Outdoor space, access to nature, for all the building’s users and anyone entering the site, were essential to the vision,” he says. The outdoor space was not only important for the development, but its connection to the wider area. “We’re starting to see that already with the elevated pedestrian connection to the High Line we’ve designed.”

The public space as a whole forms a series of “urban corridors” running along West 31st and West 33rd Streets. Manhattan West’s central plaza then picks up where West 32nd Street ends, at Penn Station on Seventh Avenue. “Together, these urban connections redefine the streetscape and help bring a new destination to life,” Van Holsbeke says. This has been bolstered by other improvements locally, including concourse upgrades at Penn Station and the transformation of the James A. Farley post office building into Moynihan Train Hall, which SOM also designed.

Manhattan West had its formal opening in late September 2021, after just over a decade of work. The majority of the development had been completed prior to the pandemic, and the elements that weren’t – Two Manhattan West, the Pendry, and retail podium and plaza – remained on schedule thanks to Brookfield’s quick response and organisation establishing necessary safety protocols to allow work
to continue.

So far, says Murphy, the response has “certainly been positive. The development is very much designed and planned with people in mind – as a place that makes public space its centrepiece. It will serve New Yorkers and visitors year-round.”