Pratt Center is a founding member of the Basement Apartments Safe for Everyone (BASE) campaign, which advocates for a legal pathway for converting New York City basements and cellars into safe, healthy, and affordable apartments. The campaign won the East New York Basement Pilot in 2016. We provide technical assistance to the campaign with a focus on land use and zoning analysis, communications strategy, and policy advocacy. 

Group of advocates holding signs at a press conference on the steps of City Hall
Advocates gathered with elected officials at City Hall in anticipation of new legislation creating an East New York Basement Apartment Conversion Pilot program.

The intersection of New York City’s affordable housing crisis, the ongoing foreclosure crisis in communities of color, and the CoVid-19 pandemic highlight the urgency needed in creating safe, healthy and affordable housing for all, especially essential workers, immigrants, people of color, and low-income households. The creation of legal basement and cellar apartments represents a crucial strategy for maximizing NYC’s existing small residential housing stock in order to do this. However, current city policy makes this almost impossible. By creating a citywide policy that allows for basement and cellar conversions (based off of the East New York Basement Pilot structure) there is a potential to produce up to 200,000 new apartments. Almost every community in New York City would benefit from such a policy. 

After success in launching the Pilot and a commitment from Mayor de Blasio to expand it Citywide, the financial devastation wrought by the CoVid pandemic to the City budget ended up setting back the pilot as it was defunded in a short-sighted move by the Mayor. Our current work focuses on building the political will and community backing to fight for what we know is a vital tool for the City to overcome the myriad crises low-income homeowners and tenants face around housing stability.

Group poses on the steps of City Hall holding signs that read: "Basements Keep East New York Safe-Stable-Affordable", and "Basement Apartments=Affordable, Safe, Stabilizes Homeownership, Prevents Homelessness, Protects Tenants, a place to call home"
Members of the BASE coalition created signs reiterating the importance of basement apartments at a February 13 press conference in 2019.

Our ongoing work includes:

  • Serving as a member of the BASE Campaign steering committee alongside Chhaya CDC, Cypress Hills Local Development Corporation, Queens Legal Services, and the Center for NYC Neighborhoods. 
  • Ongoing technical analysis of zoning and building codes that impact the ability of homeowners to create legally recognized apartments. 
  • Representing the BASE Campaign on a statewide coalition creating legislation to allow for the construction of Accessory Dwelling Units across New York State
  • Providing communications design and support for the Campaign, including the creation of flyers, presentations, and images for social media campaigns, along with social media support.

Contributions & Milestones

  • Our 2009 report New York's Housing Underground: A Refuge and Resource documents the neighborhoods with the greatest need and articulates some of the basic components of a successful policy in New York City.
  • From 2016-2018, we helped the Coalition for Community Advancement in East New York win a Basement Conversion Pilot through the neighborhood rezoning, then participated in a Task Force of City agencies and community-based advocates which crafted legislation creating the East New York Pilot  
  • In Summer 2020, Pratt Center debuted our online Basement Apartment Mapping Portal and User Guide.
  • Pratt Center developed and designed BASE’s 2021 Blueprint for Basement Apartments (see below), which incorporates four pillars of policy change into a series of one-pagers to provide elected officials, political candidates and the press with synopses of the most important changes needed to bring a successful basement legalization program to New York City.
BASE logo shows the word BASE within the outline of a house with one side open

Project Status



  • Policy
  • Research & Analysis



  • Citywide