• 95 percent of illegal dwelling units are in neighborhoods in the outer boroughs, in Queens, Brooklyn, and the Bronx.
  • A survey of one community in Queens showed that nearly 82 percent of homes showed signs of having an “illegal conversion,” and of these 35 percent could possibly be legalized.
  • These units are a critical source of affordable housing for low-income, often immigrant tenants; allowing tenants to stay in their communities, near employment and social networks.
  • These units are an important source of income for homeowners, helping many avoid foreclosure or provide space to house extended family.



Start-Up City: Growing New York City’s Entrepreneurial Ecosystem for All (PDF): Manhattan Borough President Scott Stringer’s December 2012 report with attention to section V.2, “Reform NYC Code to Allow Accessory Dwelling Units” (page 26).


Illegal Dwelling Units: A Potential Source of Affordable Housing in New York City (PDF): Chhaya CDC’s 2008 report on illegal dwelling units to New York City’s Department of Housing Preservation and Development.


New York’s Housing Underground: A Refuge and Resource (PDF): Pratt Center for Community Development and Chhaya CDC’s 2008 report.


Background Guide on How to Legalize Cellar Apartments in New York City (PDF): A report from Stein Scholars at Fordham University School of Law in connection with their enrollment in the Public Interest Lawyering Advanced Seminar.

Center for Urban Pedagogy’s BASE Comic: A graphic representation explaining the issue.