53W53 Recognized with 2019 ACEC New York Engineering Excellence Award

WSP USA served as the structural engineer for 53W53, a residential high rise in Manhattan honored by ACEC-New York with a 2019 Diamond Award for Engineering Excellence in structural systems.

NWS-HinesUS_00123NEW YORK — 53W53, formerly known as the MoMA Tower (or Torre Verre), was honored by the American Council of Engineering Companies (ACEC) New York with a 2019 Diamond Award for Engineering Excellence in structural systems.

WSP USA, a leading engineering and professional services consultancy, served as both the structural engineer of record and the provider of mechanical, electrical and plumbing engineering services for the 1,050-foot tall high-rise. Located in the heart of Midtown Manhattan, and occupying a 17,000-square-foot midblock lot between Fifth and Sixth Avenues, with access from both 53rd and 54th Streets – the 53W53 project was conceived by Developer Hines and designed by Jean Nouvel. The construction manager on this project was Lend Lease.

The slender, high-rise pyramid houses 728,000 square feet of ultra-luxury residential condominium apartments. The complex includes amenities such as a 65-foot long lap pool, wellness center, wine vaults and a private lounge with Manhattan skyline views, as well as 50,000 square feet of additional gallery space for the Museum of Modern Art.

The building tapers at gently shifting inclines. Randomly spaced diagrids – a framework of diagonally intersecting beams on the exterior of the building – roam freely up the façade, to be reflected in the unique geometry of each of the 139 apartments. But the diagrid structure is not only an aesthetic flourish. The slenderness of the building means that there is no room for superfluous structure: high-strength concrete and reinforcing steel was used to construct a shear-wall core, but the façade plays an important supporting role too.

This presented an interesting challenge for the engineering team, because architect Jean Nouvel was sensitive that the building’s complex façade should be a genuine expression of the structure beneath. “Normally we are the ones dictating where the columns go, but this was the opposite,” said Gustavo Oliveira, vice president at WSP in New York. “We couldn’t add diagrids in, we had to mimic what was on the façade, so it was an iterative process with the architect. We had never approached a building that way before.”

The other unusual feature of 53W53’s diagrid structure was the material itself. Nouvel’s original design was intended to be built in steel, but the floor-to-floor heights of a steel structure would have limited the number of stories too much. So WSP investigated how to create the same aesthetic in concrete instead, and Oliveira said it became “the first time that a diagrid structure of this magnitude and complexity has been done in concrete.”

Aside from the complex structural gymnastics, the team also spent considerable time evaluating how 53W53 could actually be delivered. Because of its complexity, construction took more than five years, around double the program for a more conventional design. One of the biggest challenges was designing the nodes where different structural components would join. Reinforcement for perhaps seven or eight elements had to fit into the same node, and then the concrete had to be able to flow freely to enclose it and produce a sound structure. Oliveira’s team worked closely not only with the architect but the construction team, and this included commissioning a mock-up of the rebar.

“Rather than just coming up with solutions that looked good on paper, we assessed the constructability of the job too, Oliveira said. Although not typically part of the engineer’s role, this is such a unique building, it needed a unique approach.”

About WSP USA

WSP USA is the U.S. operating company of WSP, one of the world's leading engineering and professional services firms. Dedicated to serving local communities, we are engineers, planners, technical experts, strategic advisors and construction management professionals. WSP USA designs lasting solutions in the buildings, transportation, energy, water and environment markets. With more than 9,500 employees in 150 offices across the U.S., we partner with our clients to help communities prosper. wsp.com