Authorities ordered the evacuation of streets and buildings in part of Midtown Manhattan, New York City, on Tuesday 7 July over fears that a 37-storey office tower being converted to apartments was about to collapse.
The steel-frame building at 235 East 42nd Street between 2nd and 3rd Avenues used to be the headquarters of pharmaceutical giant Pfizer but is now being converted to house 1,600 apartments by developer MetroLoft. It has been billed as the biggest such conversion in the US.
New York Fire Commissioner Lillian Bonsignore told a media briefing that the Fire Department of New York (FDNY) received an emergency call at 7:57am Tuesday reporting bricks falling from upper floors.
On arrival, crews determined the building was unstable and established a “frozen” zone, evacuating workers from the building and people from seven surrounding buildings.
Buckled structural columns
New York City Mayor Zohran Mamdani told the media briefing that the city’s Department of Buildings had found structural issues on the 21st floor, where two structural columns had buckled. There were also multiple cracks and sagging floors, he said.
Ahmed Tigani, Department of Buildings (DOB) Commissioner, said: “We have seen both buckling and floor conditions that are impaired on the 21st floor. We both have construction, safety inspectors and construction safety engineers on-site evaluating from the street and vantage points across the street and to the west so we can monitor movement of the building and the floors to understand what’s happening on a continuous basis.
“Once we can determine that it’s safe to enter the building, we will then, in concert with the contractors, ownership, and with consultation with FDNY, be able to deploy a plan to shore up that floor and then continue to investigate further for any other weak points that need further help and shoring.”
‘Exhaustive review over two years’
One reporter asked Tigani whether an 11-storey addition to the building from the existing 22nd floor – which created a separate extension – could have caused the columns to buckle.
Tigani said the project went through “an extensive, exhaustive review with DOB over the last two years”, and that the precise cause of the failure was being investigated.
Later in the day, workers entered the building to shore up the 21st floor, working through the night.
Late on Tuesday, Tigani told media: “I can say right now the building is stable. We feel confident in the emergency plan we have now.”
Too early to speculate
“Structural problems of this nature are always sui generis, which means they always have facts that, when fully exposed, will be unique to the situation rather than representative of a common type of problem that is readily duplicated.”
He added: “These types of failures are quite uncommon but each one helps to build an even bigger reservoir of examples for future projects to learn from.”
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