The buckling of columns in a high-profile office tower in New York City undergoing a conversion to residential use reflects the weight and stress challenges property owners can face as they look to add space to capture shifting demand, architects and designers say.
Fire inspectors called to the 37-story former Pfizer headquarters in Manhattan at 219-235 E. 42nd St. on Tuesday found two columns that buckled on the 21st and 22nd floors and sagging floors between the 21st and 26th levels, prompting an evacuation of the building and nine nearby structures; there were no reported injuries.
While the city had not released findings from an examination of the structure as of late Tuesday, possible causes of the buckling and sagging floors can include “an unanticipated concentration of loads, temporary construction loading and damage during construction activities,” said Joe Mamayek, an architect and principal at SGA in Boston who has designed tall buildings and is not involved in the New York project.
The building between Second and Third avenues near Grand Central Station will be the largest office-to-residential conversion in New York history upon completion, estimated for next year, according to San Francisco-based Gensler, the architectural firm on the project. Plans call for creating "1,600 apartments, including over 400 affordable housing units, and will feature over 100,000 square feet of amenities, a rooftop pool, a fitness center, ground-floor retail and offices," Gensler said on its website.
All that added weight can cause unanticipated stress, Mamayek and other design professionals told CoStar News. And co-developer Metro Loft Management told the Wall Street Journal on Tuesday the weight of an addition on top of the building likely caused the partial collapse.
Problems elsewhere in city
It's just the latest problem with a large residential project in New York City.
A tower was recently abandoned due to structural concerns and appears to be leaning and in danger of falling, according to architects who work in the city.
The construction of the 670-foot-tall Seaport Residences at 161 Maiden Lane was halted in 2020 and it remains unfinished, according to media reports. Building owner Fortis Property Group didn't respond to an email seeking a comment.
The condominium board at 432 Park, a 1,396-foot-tall residential tower in Manhattan, sued developers CIM Group and Harry Macklowe over construction defects, according to media reports. CIM and Macklowe have denied the accusations and say the building is structurally sound.
Following the pandemic, a number of owners of outdated office towers pursued converting their properties to residential as worker attendance dropped and housing remained in high demand. An office-to-residential conversion in and of itself doesn't pose a significant safety risk in terms of construction requirements but how it's executed is vital, said Mamayek.
In particular, designers and construction firms usually don't need to relocate essential columns that carry loads and provide structural support, he said. “The existing column spacing in an office building is generally adequate for a conversion to residential use and there is typically no need to relocate primary structural columns,” if designed by experienced architects and construction professionals, Mamayek told CoStar News.
Unanticipated load concentrations are “extremely rare,” said Eugene Gurevich, a principal and structural engineer at Rand Engineering & Architecture in New York who is not involved in the Pfizer building project. “There are many precautions in place to prevent this kind of thing.”
An adaptive reuse of an older building to a new use, such as office-to-residential, does not make a construction project more prone to problems, Gurevich said.
Causes not yet known
The city of New York Department of Buildings has received complaints about the construction project since last year, such as debris falling to the street, according to media reports.
The city’s building department last inspected the site on May 15 and “found no unsafe conditions,” David Maggiotto, a department spokesman, said in an emailed statement. The city of New York’s construction code is the “most comprehensive” of its type in the U.S., he said.
Engineers completed their initial assessment of 235 E. 42nd on Tuesday afternoon and found no additional movement in the damaged columns, Maggiotto said. With monitoring of the affected area ongoing, the team determined contractors can proceed with installing temporary shoring to stabilize the building.
Gensler, the lead design architect and architect of record for the conversion, referred questions to co-developer Metro Loft Management. Metro Loft declined to comment on building findings to CoStar News. A joint venture between Metro Loft and David Werner Real Estate Investments is the project developer.
The development involves the conversion of two separate buildings, according to a project description on the Gensler website. The project will add 19 stories on top of the original 10-story structure at 219 E. 42nd St. and reconfigure and reclad the 33-story building at 235 E. 42nd St.
Potential challenges ahead
It's likely to take months before discovering the underlying reasons for the loads that caused the sagging and buckling, said Barry LePatner, a New York-based attorney who handles construction cases and wrote the book “Broken Buildings, Busted Budgets: How to Fix America’s Trillion-Dollar Construction Industry.”
“The city is going to bring in outside experts and insurance companies are learning they might have to pay and they will bring in their own experts,” LePatner said.
City officials make safety at construction sites a top priority, but it’s extremely difficult to identify and analyze all the most-minute details, as building inspectors can't be on-site at all times, Mamayek said.
“This is always a major public safety concern, both for the general public and for workers on the construction site,” he said.
The financing
In August 2024, a joint venture between affiliates of Metro Loft Management and David Werner Real Estate Investments, which is redeveloping Pfizer’s former office space at 219 E. 42nd St. and the adjacent 235 E. 42nd, closed a $75 million senior mortgage acquisition predevelopment loan backed by 219 E. 42nd, said Northwind Group, a Manhattan-based real estate private equity firm that provided the financing.
Metro Loft was founded by Nathan Berman in 1997 and has played a significant role in the office-to-residential conversions in lower Manhattan, Northwind said.
Northwind recently also gave a $95 million acquisition loan to David Werner and its partner BLDG on the joint venture’s purchase of the 515,000-square-foot 100 Wall St. office property in lower Manhattan’s Financial District that brokers involved have said also has a planned residential conversion.
CoStar News reporter Andria Cheng contributed to this story.