As New York City continues to grow, demand for housing has led to a dramatic expansion of the city’s informal housing market. Housing advocates estimate that there at least 114,000 apartments that are not reflected in the official number of certificates of occupancy granted by the City and are, therefore, not approved for use as living spaces. This number is likely a very low estimate.

Overcrowding, a scarce supply of affordable housing, inflated housing prices, and a housing gap have led to a surge in unapproved apartments throughout the city, with the highest rates occurring in the borough of Queens. Today, many have become home to new immigrants seeking housing during the city’s ongoing affordable housing crisis.


Due to archaic building codes, the majority of New York City families cannot currently use their basements to house their own family members or as rental units to support their own income. The Basement Apartments Safe for Everyone (BASE) campaign proposes that New York City remedy this by adding a new category of residence to building, housing, and zoning codes creating an “Accessory Dwelling Unit” (ADU) code.

The New York City Ordinance on Accessory Dwelling Units defines “accessory dwelling unit” as a residential living unit that provides complete independent living facilities for one or more persons, including permanent provisions for living, sleeping, eating, cooking and sanitation on the same parcel as the single-family dwelling it accompanies.

Along with establishing the ADU code, the city would:

  • Legalize safe units, even in areas that are currently zoned to limit housing to single-family residences.
  • Keep units affordable by creating a conditional tax incentive for owners.
  • Launch a pilot project in targeted communities with high rates of foreclosures and overcrowded schools for an accessory dwelling unit conversion program.
  • Provide technical and financial assistance to homeowners who participate in the pilot program.


To protect tenants: Tenants in basement units are often the most vulnerable to poor living conditions and face the highest risk of displacement. Because their units are illegal, many avoid using the court system when seeking improvements or assistance with harassment issues. Allowing for the legalization of safe basement apartments would provide additional protections for these tenants, who currently have no recourse in housing court.

To increase affordable housing: It is commonly known that New York City is facing a housing crisis. Over 11 percent of all rental housing is considered overcrowded. In 2005, one out of four households spent over half their income on housing. Basement units are the largest source of safe, affordable, and sustainable housing to accommodate our city’s growing population.

To prevent foreclosures: Owners who illegally rent their basement units can face fines of up to $15,000. Many of these homeowners are victims of predatory lending whose homes are at risk of default. In neighborhoods such as Southern Queens, loss of rental income is contributing to the rise in mortgage defaults. Allowing homeowners to rent out basement units would supply owners with rental income that would prevent foreclosures and stabilize neighborhoods.


Many municipalities in the U.S. have adopted the concept to allow ancillary apartments in single-family districts, including California, Illinois, Massachusetts, Oregon and Washington, D.C. To accomplish this we need to:

  • Establish nonprofit partners to administer and support implementation of program and ensure compliance.
  • Provide financial and technical assistance for compliant owners including a grace period during which some fees and fines would be waived.
  • Ensure that existing tenants priority to remain in unit after legalization.
  • Ensure that rents remain affordable in order for owners to benefit from the program.