Work has been halted at one of the largest office-to-apartment conversion projects in the United States after two steel columns buckled inside the former Pfizer headquarters in midtown Manhattan. The incident, which prompted evacuations and is currently under investigation, underscores the engineering challenges inherent in adaptive reuse projects.
Adaptive reuse has gained traction as a strategy to combat a nationwide housing shortage by transforming underused office buildings into residential units. The Manhattan project aims to convert two office buildings, one dating to 1909 and the other to the 1960s, into approximately 1,600 apartments. This involves adding more than a dozen stories to the older structure and reconfiguring the newer one. The buckling occurred on the 21st floor of the more recent building, and temporary supports have been installed.
Engineering experts suggest that while such conversions are complex, the setback at the Pfizer building does not fundamentally question the capability of engineers to execute these projects. Ben Schafer, a structural engineering professor at Johns Hopkins University, stated that the incident does not call into question the understanding of how to perform such work. The firm managing the project, Collaborative Construction Management, has described the 1909 building's conversion as involving the integration of a new, approximately 30-story addition.
Structural engineers anticipate that the approach for the older building likely involves leaving its original structure to support its own weight while a new structural system is erected to bear the load of the added stories. For the 1960s tower, the challenge lies in modifying the existing floor plates to allow for residential living spaces and natural light while ensuring the steel frame can manage the new weight.
While the exact cause of the column failure has not been determined by city officials, both Schafer and San Francisco-based structural engineer Emily Guglielmo believe the added load during construction was a probable factor. Nathan Berman, founder of the project developer MetroLoft, acknowledged to The Wall Street Journal that the increased weight from widening the upper portion of the building likely contributed to the damage. Guglielmo noted that potential issues could stem from misinterpretations of original design assumptions, errors in the design or construction process, or the structure being overloaded or weakened during construction.
Adding stories to existing buildings is a common practice in densely populated urban areas where land is limited. This process requires a thorough review of original construction documents and a detailed inspection of the building to assess how new loads will impact the structure. Guglielmo highlighted that in areas lacking available land, adaptive reuse of existing buildings is a prevalent design strategy.
From a sustainability perspective, demolition is often seen as a last resort. Schafer emphasized that constructing new buildings and the associated sector contribute significantly to global carbon emissions, making demolition an environmentally detrimental choice, particularly in expensive urban centers like New York.
Officials across the U.S. have increasingly supported office-to-housing conversions as a means to revitalize downtown business districts impacted by shifts in work patterns since the pandemic. New York City, in particular, has pursued this initiative through zoning changes and tax incentives. A report from the New York City comptroller's office indicated that as of early 2025, there were 44 adaptive reuse projects in the city that were completed, in progress, or slated to move forward.
The former Pfizer building became vacant when the company relocated its offices in 2023. Construction on the conversion project began in 2024. Joshua Harris, director of Fordham University’s Real Estate Institute, views these conversions as critical for addressing housing shortages, even with the associated risks. He described these projects as "surgical procedures" on older buildings, noting that complications can arise, but they are part of the reality of tackling the housing crisis.
Despite the challenges, Harris pointed out that robust building codes, thorough inspections, and experienced construction crews contribute to the rarity of such failures in the United States. He suggested that the incident may prompt a review of other similar conversion projects currently underway or approved.