425 Park Avenue: a citadel of finance, opens for business in New York

Following a symbolic ribbon-cutting ceremony in late October, 425 Park Avenue, the latest office building in New York City, is now open for business. Occupying a full block on the east side of the grandest avenue in Manhattan, between 55th and 56th streets, this 47-storey tall and just a few feet shy of a 900-foot mark building is a product of the remarkable ambition and vision of its developer, L&L Holding Company and architect, Norman Foster. The one billion dollar building is conceived as a chic stack of three glass blocks, each with a smaller footprint and increased height as they rise. The lower volume reinforces the street edge; the other two are set back both from the front and the sides. Unlike the traditional ‘wedding cake’ New York towers, the building’s tiers are separated by two triple-height gaps in between and are prominently tied by a handsome exoskeleton, clad in gleaming steel. The two setbacks at floors 12 and 26 are celebrated by expressive structural diagrid with outdoor landscaped terraces. The higher of the two is reserved for the Diagrid Club with a wellness centre and an open-plan cafeteria highlighted by a lengthy Yayoi Kusama wall installation; this airy space with knockout views of the city is open to all tenants. 

The new building is also noteworthy for how it meets both the ground and the sky. The ground floor along the Park Avenue side, a dramatic 45-foot-high space, is divided into three roughly equal parts of close to cubic forms—the lobby at the centre is lined in stone flooring, back-painted glass walls, a clean-cut combination of flat and corrugated steel panels of various patterns and finishes, and recessed overhead lighting. The centre of the back wall of this serene silvery-tone space, behind the reception counter, soon will be accented by a 24-foot-tall colourful painting by American abstract expressionist Larry Poons. The lobby is bookended by a restaurant to the north and a commercial space to the south, both still in construction. Although the building is not among the tallest in New York, its distinct crown, a trident of 136-foot-tall illuminated blades, makes it one of the most iconic spires on Manhattan’s skyline. Designed as extensions of three central shear walls, this symbolic feature makes the building visually complete while proclaiming its civic grandeur, not merely a commercial one.

The story of the creation of 425 Park Avenue rests on two important factors. First, this building was in the making for many years—18 to be precise. The result is not an entirely new structure but a thorough redevelopment of the original 1957 property. Secondly, Foster’s vision was a winning scheme in an international competition, in which the world’s leading architects competed. Let me start with the competition and then highlight the intricacies of this project’s redevelopment to better understand the nature of complexity that involves building in New York. To be noted—constructing an architectural masterpiece here is just one piece of an intricate real estate puzzle.

The competition commenced in April 2012, when 11 internationally-acclaimed architects were sent requests for qualifications. Among those selected, 10 were Pritzker Prize laureates. 2012 was an optimistic era when America finally came out of the 2008 global financial crisis and was showing strong signs of economic expansion. By May four finalists were announced—three Brits and one Dutchman—Norman Foster of Foster + Partners, Richard Rogers of Rogers Stirk Harbour + Partners, Zaha Hadid of Zaha Hadid Architects, and Rem Koolhaas of OMA. Their in-person presentations were video recorded and widely discussed in professional and popular media; these penetrating testimonies can still be viewed on YouTube. They give rare insights into how our leading practitioners defend their work and why Norman Foster won this competition, I would add, with ease.   

While Hadid and Koolhaas defended their highly sculptural solutions by focusing almost entirely on the qualities of their forms and skins, Foster and Rogers presented their buildings to both celebrate modernity and explore various office layouts. Both included such desirable amenities as hanging gardens. All four proposed original diversions from typical New York City wedding cake tower typology, but only Foster went into detail on what kind of spaces his client would be getting. His building was not just spectacular but versatile. He playfully mentioned the precise dimensions of his floor plates assuring everyone in the room that he personally was behind every decision and drawing discussed; he was. If the client were to choose him, his involvement would be complete. In early October, he won the commission.

The scheme Foster presented is almost identical to what was ultimately built. What did not materialise is how he envisioned the building’s engagement with the public realm at the ground level, where he proposed to devote much of the ground floor area to an outdoor plaza with changing exhibitions of world-class sculptures. This unfortunate omission certainly makes the building so much less of a great asset to the public than it originally aspired to. In that sense, the new structure is not on par with such nearby New York icons as—the Seagram Building by Mies van der Rohe and Lever House by Gordon Bunshaft with their popular outdoor plazas or Philip Johnson’s 550 Madison (formerly AT&T Building) with its original public annex, which is now converted into an outdoor covered garden.

Among the most impressive parts of Foster’s building, expectedly are dazzling spaces and views offered from within the diagrid. These very special moments celebrate urbanity in ways that very few places around the world can match. Triangulation used here is not only geometrically more adventurous and daring than conventional orthogonal structures, but it allows for a more economical use of steel. Along with the soon-to-be-finished new global headquarters for JPMorgan Chase, also on Park Avenue, rising steadily just seven blocks south from here, and the Hearst Tower built near Columbus Circle in 2006, 425 Park Avenue is one of three buildings in the city where the architect explored structural triangulation. This trio goes beyond individual style, serving as a great example of a new attitude toward building high. It is such a clever use of a structure that allowed Foster’s building to achieve entirely column-free spaces on floors 28 and up. Larger mid-rise open-plan floor plates are interrupted by only five columns and the largest lower floors feature six columns, 30 feet apart.

All floor plates are flexible, well-proportioned rectangular spaces that allow endless interior layouts, while adjacent floors can be linked or combined. This spatial versatility was enabled by moving the core—elevators, stairs, and mechanical spaces—to the back and stretching it along the east side. This clear articulation of ‘served’ and ‘servant’ spaces that Louis Kahn had demonstrated in his Richards Medical Research Laboratories completed in Philadelphia in 1965, essentially a low-rise building, was first used in a tower configuration by Foster in his very first skyscraper architecture project, HSBC Headquarters in Hong Kong in 1979. When I interviewed the architect at his London office in 2008, he said about his own precedent, “I still find it extraordinary that this was the first attempt in the history of the skyscraper that someone questioned and dissolved the centre core and moved it to the edges. Once you do that you have greater potential for served floor voids and the ability to break down uniformity vertically to create interruptions in terms of double-height spaces.” Additionally, the back core is recessed at both ends to enable all floor plates to retain glass corners. In fact, all four corners at each level are glazed and uninterrupted by structure, which causes a sensation as if you are surrounded by 360-degree views. The building’s envelope is so convincing that the open corners and ‘missing’ columns are taken for granted. At least it seemed so to me. It was only after the visit to one of the higher-up floors, when I was examining my own photos, that I realised, “Wait a minute, where is all the structure?” 

As mentioned earlier, this building was in the making since 2004, when L&L Holding first attempted to redevelop 425 Park Avenue when it was still occupied by the original building standing here since 1957. In 2006 the developer acquired the lease to redevelop the site after the existing leases with the building tenants would expire in 2015. In the meantime, the competition was held. To complicate things, we need to understand that not only did the new building have to project the right spirit, but it also had to work with the existing building. Here is why. According to the 1961 zoning regulation, this site could fit a maximum of 580,000 square feet of new space, which is less than the original building had—670,000. However, there was a way to go around the 1961 zoning rules. If the developer could retain at least 25 per cent of the pre-1961 original structure, the new building would be permitted to build up to the original square footage. 

The decision was made to keep a quarter of the 1957 building. But to incorporate the original 32-storey structure with a different footprint, configuration, column grid, and lower ceiling heights, is easier said than done. The first step was to demolish the top 15 floors. A temporary steel structure had to be installed to support the remaining 17 floors before further demolition below and around. Then 12 new jumbo columns were erected, six at the front of the new building (they make up the base part of the exoskeleton) and six at its centre. The new core was built in the rear to connect to every other of the remaining 17 floors. The rest of the unconnected floor slabs were removed to achieve double-high ceiling floors at the base (I am curious how often the 25 per cent number was recalculated). The temporary structure had to be put in place before permanent new floors were built atop the old ones.

It helped that the anchor tenant, Ken Griffin’s Citadel, a global investment firm, signed the lease in early 2016, shortly after the construction started. At the time, it became the most expensive lease in the city’s history. The tower was topped out by late 2018. Eventually, the company agreed to lease more space, now leasing half of the building, including the penthouse, Griffin’s own glass office with surely the most magical urban views right under his feet and across the table, with the ceiling hovering at an improbable height of 42 feet. This extraordinary space in the sky sits at the foot of the building’s signature pinnacle. When Norman Foster finished his presentation, he came to his model, removed the top, looked into the eyes of the members of the jury, and said, “I am not saying this is the final flourish to the building. And it is an honourable building without it.” He paused, firmly placed the pinnacle back, and nailed his presentation: “But once you become accustomed to seeing something like this, it suddenly looks sort of undressed as a building.”