New York City Mayor Zohran Mamdani has said he wants to freeze rents for roughly 1 million rent-stabilized apartments and sharply expand affordable housing production, but one of the city’s most ambitious proposals—the Sunnyside Yard rail-yard deckover plan in Queens—has not moved forward since its 2020 release as the pandemic began.
New York City’s rental market remains exceptionally tight. The city’s Department of Housing Preservation and Development reported a 1.4% net rental vacancy rate in the 2023 Housing and Vacancy Survey—its lowest level since 1968—a statistic that policymakers and advocates have cited as evidence of a continuing housing emergency.
One of Mayor Zohran Mamdani’s most prominent campaign pledges was to seek a rent freeze for tenants in the city’s roughly 1 million rent-stabilized apartments. The mayor cannot impose that unilaterally: rent increases for stabilized leases are set annually by the nine-member Rent Guidelines Board, which is appointed by the mayor but is widely described as operating independently and basing decisions on economic data. Under Mayor Bill de Blasio, the board approved rent freezes in 2015, 2016, and 2020.
In a February 2025 position paper, Mamdani also pledged to significantly expand affordable housing production, including a goal of constructing 200,000 publicly subsidized, permanently affordable, union-built, rent-stabilized homes over 10 years, and another 200,000 affordable homes over 10 years financed with city capital funds.
New York leaders regularly describe housing results using a combined accounting of units built, preserved, and planned for, a practice that has drawn criticism for blurring what has been completed versus what is still projected. In an example cited by The Nation, the Adams administration said it “built” or “preserved” 33,715 affordable units in fiscal year 2025, and stated that by the end of a single term 425,000 units “will have been built, preserved or planned for.” De Blasio’s administration said it created more than 66,000 affordable units and preserved 134,000 more over two terms.
A long-discussed opportunity is Sunnyside Yard, a roughly mile-and-a-half-long rail yard in Queens that the Sunnyside Yard master plan described as 180 acres. The 2020 master plan, drafted by Practice for Architecture and Urbanism (PAU), proposed decking over the yard and building 12,000 new 100% affordable residential units, alongside 60 acres of open public space, a new Sunnyside Station, 10 schools, 2 libraries, more than 30 childcare centers, 5 health care facilities, and 5 million square feet of commercial and manufacturing space.
The plan was released in early March 2020, just as the Covid-19 shutdown began, and it has since become “completely dormant,” PAU founder Vishaan Chakrabarti told The Nation. Chakrabarti said the project would require rezoning and that a commuter rail station would be needed to help catalyze development. He also argued that building the platform over the yard would require a major federal grant, and he criticized Mayor Eric Adams for not pursuing federal infrastructure funding during the Biden administration while the plan was still prominent.
Separately, The Nation noted that large-scale development in New York often unfolds over decades, while mayors generally serve a maximum of eight years, adding pressure for administrations to build on projects already in the pipeline.
Mamdani may inherit one such pipeline from Adams: the citywide rezoning package known as “City of Yes,” which The Nation said is projected to generate 82,000 homes over 15 years by encouraging infill development such as accessory dwelling units, smaller apartments, and modest new housing in commercial corridors.
Developers and housing experts interviewed by The Nation warned that, even with new zoning tools, financing and approvals for affordable housing can take years, while existing affordable units can be lost through deterioration, conversion, or other pressures. NYU Schack Institute’s Marc Norman told the magazine that a new mayor’s success often depends on leveraging what prior administrations have already set in motion.
