Structural columns buckle on 21st floor of Manhattan adaptive reuse project | Dump Trucks Charlotte NC

Listen to the article 5 min

This audio is auto-generated. Please let us know if you have feedback.

Compromised structural beams on the 21st floor of a Manhattan construction site caused several evacuations and road closures Tuesday, the New York City Department of Buildings confirmed to Construction Dive.

Two structural columns have buckled, multiple cracks have formed and floors have sagged, Mayor Zohran Mamdani said at a press conference with other city officials. 

“The building remains unstable. Since arriving on-scene we have witnessed additional movement in one of the compromised columns,” Mamdani said.

Department of Buildings engineers are monitoring the structure — a commercial office to residential conversion project — with fire department drones, the mayor said. The city’s team will eventually seek to shore up the columns if the floor is deemed stable and safe enough to do so.

Dangers and concerns

Video shot by jobsite workers shows buckling supports at the project. 

Joe DiPompeo, president of New Jersey civil engineering firm Structural Workshop, said he has driven past the East 42nd Street building on multiple occasions. After watching the posted videos of the interior, he called the failed beams “very concerning.” He also noted metal studs for interior walls were buckling as well.

“The only thing that really would cause them to buckle, because they're not load-bearing, is if the floor above comes down and loads them. I suspect the floor above dropped when those main columns buckled and buckled the studs, which is not good,” DiPompeo told Construction Dive.

Also the former president of the American Society of Civil Engineers’ Structural Engineering Institute from 2020-2021, DiPompeo posited that the support columns probably failed first. 

A number of factors could have caused the failure, he added.

For example, stacking construction materials in an area not designed for a heavy load, or if a crew diverged from the design plans and cut into a structural support, perhaps for electrical or plumbing work.

Fixing this problem is a major undertaking.

“Best case scenario is you get it shored, then you've addressed the problem temporarily,” DiPompeo said. “But if that floor above dropped a foot or two, which looks like what would've happened with the amount of movement and the columns and the studs, the top 10 stories of this building are now crooked.”

DiPompeo said he struggled to imagine how the building could be safe enough to shore up the columns from the inside, but considered crews potentially working from a large crane from the outside of the building.

“If this floor gave way, you got 10 stories coming down on top of 22,” DiPompeo said. “You certainly can see why they evacuated the building and the area and are taking it as seriously as they are.”

In the meantime, officials repeatedly stated they plan to monitor and shore up the building for further investigation, but would prioritize keeping people safe.

“The way this building is constructed, it's a steel frame building so it would not be a total collapse, it would be more of a localized collapse, ” said Fire Department of New York Chief John Esposito during Tuesday’s press conference.

All construction workers were accounted for after evacuation, Mamdani said.

Project details

The residential conversion — the former headquarters for Pfizer — is being developed by Metro Loft with 235 GC listed as general contractor, according to DOB documents shared with Construction Dive. Gensler is the project architect, and adaptive reuse firm Collaborative Construction Management lists the project on its website.

With a projected finish for 2027, the reuse project represents the largest office to residential conversion in New York City’s history, according to Collaborative Construction Management’s website. The 1.3 million square foot structure would create 1,600 luxury apartments, per plans from Metro Loft.