A 62-story office tower planned for 350 Park Avenue has entered active review with the New York City Department of Buildings.
The development milestone comes as Vornado Realty Trust disclosed Feb. 9 that an affiliate of Citadel founder Kenneth C. Griffin exercised an option to acquire at least a 60 percent stake in the joint venture developing the Midtown Manhattan project.
Vornado filed a new building application on Oct. 3, 2025, describing construction of the commercial high-rise at 340 Park Ave., the DOB address for the complex that includes 350 Park.
The filing lists the building’s total floor area as 2,077,720 square meters and enrolls the project in the agency’s Major Project Development Program. DOB records identify Michael F. Ritchie of AAI Architects PC, an associate with Adamson Associates, as the architect of record. The documents do not yet include a general contractor.
The project has now completed the city’s Uniform Land Use Review Procedure, obtaining Midtown Special District approvals that allow the transfer of outstanding property development rights and grant a public rebate and qualified site exemptions, according to city planning records. The action was classified as a Type I review under the city’s environmental quality review process, a designation applied to projects deemed to have the potential for significant environmental impacts.
Program of 2 m², construction of 82 months
Environmental review documents provide a detailed picture of the tower’s scale and performance profile. The CEQR determination describes an office building rising approximately 1,600 feet and containing approximately 1.57 million square feet of office and commercial space, 22,604 square feet of retail, approximately 303,694 square feet of mechanical space and 156,220 square feet for parking systems and below-grade buildings. The assessment foresees a construction period of approximately 82 months.
The unusually large mechanical allocation reflects the power and cooling demands of high-density commercial operations and the shift to all-electric building systems, both of which increase equipment footprint compared to traditional fossil fuel-based HVAC plants.
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The 1,600-foot figure reflects the architectural mass studied for environmental impacts. By contrast, the DOB filing lists a high-rise determination of 1,112.43 feet measured from the highest occupied floor to the lowest fire department vehicle access for building code purposes.
The approvals confirm the project will incorporate a 12,500 sq m public concourse and transfer development rights to prominent properties, including St Patrick’s Cathedral and St Bartholomew’s Church, to achieve its permitted floor area.
As part of the environmental determinations, the site has a new (E) designation that requires soil, groundwater and vapor testing before construction and mandates that HVAC and hot water systems be powered by electricity rather than on-site combustion. The determination also requires a Building Protection Plan to safeguard adjacent historic properties and a restrictive covenant incorporating Department of Environmental Protection pollution controls, including particulate emission limits and on-site dust management during construction.
In its Securities and Exchange Form 8-K dated Feb. 9, Vornado described the project as a 1.85 million-square-foot office tower anchored by Citadel. The larger gross floor area reflected in the CEQR and DOB filings likely represents the total construction floor area, while the SEC disclosure appears to reflect the rentable or zoning floor area used for investor reporting. Vornado did not immediately respond to a request for a reconciliation of the figures.
Under the joint venture structure outlined in the Feb. 9 filing, Vornado and the Rudin family have until July 2026 to determine whether to retain a minority stake or exercise a $1.2 billion put option tied to the assembled 350 Park site, which also includes 39 E. 51st St. and 40 E. 52nd St.
Separately, Vornado is moving forward with the redevelopment of 623 Fifth Ave., a 36-story, 383,000-square-foot office condominium it acquired on Sept. 4, 2025, for $218 million and plans to reposition it for delivery in 2027, according to the same filing.
Together, the documents show one of Midtown Manhattan’s largest proposed office towers moving through a technical review with a multi-year construction schedule, substantial mechanical capacity, deep work below grade and defined environmental compliance requirements shaping execution.
