For Immediate Release: September 30, 2025
CONTACT: dobcommunications@buildings.nyc.gov, (212) 393-2126

ADAMS ADMINISTRATION OPENS APPLICATION PORTAL FOR HOMEOWNERS TO BUILD ANCILLARY DWELLING UNITS

Delivering on the Promise of “City of Yes”, Administration Publishes Finalized ADU Rules and Kickstarts Pre-Approved Plan Library 

New Type of Housing Opens More Opportunities for New Yorkers Looking For a Safe and Legal Place to Call Home

New York, NY – Mayor Eric Adams today announced that the City has officially begun accepting applications for the construction of safe, and code-compliant Ancillary Dwelling Units (ADU) in the five boroughs of New York City. To encourage homeowners who are interested in constructing a legal ADU on their property, Mayor Adams also launched today ADU For You, a new homeowner assistance program. This announcement follows the passage of the administration’s City of Yes for Housing Opportunity plan which was approved by the City Council at the end of last year. Among other significant changes to the city’s zoning rules, the City of Yes plan recognized this new category of housing in New York City for the first time, which will increase legal housing opportunities for New Yorkers in lower-density neighborhoods.

“As we work to address New York’s housing affordability crisis, it’s essential that every new unit is not only legal, but safe,” said Deputy Mayor for Operations Jeff Roth. “With these newly recognized Ancillary Dwelling Units — whether in a basement, attic, or backyard — New Yorkers can have confidence that each home meets rigorous standards for zoning, construction, fire safety, and occupancy. Every unit created under these rules will be a safe, code-compliant home that protects the health and well-being of our communities.”

“Too many New Yorkers are forced to choose between having a roof over their heads in an Ancillary Dwelling Unit or living in safe, regulated housing. New Yorkers no longer have to choose,” said Adolfo Carrion, Jr., Deputy Mayor of Housing, Economic Development, and Workforce. "Now, ADUs and the ADU for You homeowner assistance program will create more housing opportunities, keep New Yorkers safe, and make it more affordable than ever to build ADUs."

"With a vacancy rate of just 1.4% and an ongoing affordability crisis, HPD is pursuing every avenue to get New Yorkers the answers they need," said Acting HPD Commissioner Ahmed Tigani. "Today's announcement, formally opening the portal for homeowners to submit ADU proposals, is an incredible next step. ADUs are a commonsense part of the solution to an incredibly complex housing affordability problem: by allowing homeowners to develop an ADU on their property, we are building much-needed affordable housing, while giving New York City homeowners the opportunity to make more room for a beloved family member or make a bit of extra income. HPD stands ready to support anyone eligible and looking to develop an ADU on their property and help us tackle the housing crisis head-on."  

"ADUs are a proven housing solution across the country, and now, homeowners in New York will have the opportunity to add one to their property right here in the five boroughs. These new homes will help address our historic housing shortage — providing provide more housing and housing types across the city, allowing seniors to age in place, and giving middle-class homeowners an opportunity for extra income," said Dan Garodnick, Director of the Department of City Planning. "Thanks to everyone who has made this a milestone a reality, from the City Council's partnership on City of Yes for Housing Opportunity to our partners across government who have helped finalize these rules."

“This administration always puts the safety of our fellow New Yorkers at the forefront of discussions when considering changes to building regulations,” said Buildings Commissioner Jimmy Oddo. “DOB’s new finalized department rules for ADUs, crafted alongside additional rules from our agency partners, are measures that will help protect residents and uphold our core safety mission.”

“Basement apartments can only be safe in places that aren’t prone to stormwater flooding,” said DEP Commissioner Rohit T. Aggarwala. “This was a top concern throughout this process, and DEP’s flood risk maps are essential tools for guiding where ADUs can be safely built.”

"New Yorkers should live in safe environments, including when they make a basement apartment their home," said Corinne Schiff, Deputy Commissioner for Environmental Health at the New York City Health Department. "Air quality in basement apartments can create added risks to health, but new Health Department rules will set protective standards, so these residents can breathe easy. We’re proud to join with the other City agencies to promote stable, safe housing for New Yorkers."

“With the release of New York City's final ADU rules, we're opening the door to smart, sustainable housing solutions that meet the needs of our diverse communities,” said Executive Director for Housing Leila Bozorg. “ADUs are a powerful tool to create additional housing, support multigenerational living, and help homeowners build equity—without changing the character of our neighborhoods.”

Acceptable types of ADUs under new city rules include basement apartments, attic apartments in one-family homes, and backyard cottages on the same lot as one- and two-family residential homes, that can be used by household family members or rented out long-term to other New Yorkers. The city will accept applications for the construction of ADUs beginning today, September 30, 2025, through the DOB NOW: Build filing portal. The creation of this new form of housing recognizes that New York City is amid a housing affordability crisis, and creating a little more housing in every neighborhood citywide is needed to bring housing prices down. Each of these new legal ADUs must comply with comprehensive requirements for zoning, construction, fire safety and occupancy, which help protect the health and safety of occupants and their neighbors.

The ADU For You program will serve as an online, public-facing resource for homeowners, providing guidance and support on how to navigate the complexities of adding an ADU to their existing property. The program will also allow homeowners the option to pick a pre-approved ADU design from our new Pre-Approved Plan Library (PAPL), simplifying the application and approval process. Licensed design professionals can help the city grow the PAPL by submitting their own plans for potential inclusion in the library. These plans will be reviewed by the NYC Department of Buildings (DOB), and if approved they will be issued a Pre-Approved Plan Number and then added into the PAPL. Homeowners that select an ADU option from the PAPL will be able to contact the registered design professional (RDP) who created the design directly and hire that RDP to complete the project. A team lead by WXY, Habitat for Humanity of New York City and Westchester, and KM Associates is assisting the city with creating these resources. Neighborhood Restore HDFC, through its affiliate Restored Homes HDFC, will be available to provide guidance and advice to homeowners as they use these and other resources to create ADUs on their properties.

Since the passage of City of Yes for Housing Opportunity, DOB and HPD have worked closely with the NYC Department of Environment Protection (DEP), the NYC Department of Health and Mental Hygiene (DOHMH), and the New York City Fire Department (FDNY), among several other agencies, on rules promulgated by DOB, DEP and DOHMH surrounding the approval of ADUs, with a goal of prioritizing the safety of ADU occupants, other residents on the property, and members of the community. This rulemaking process included public hearings where the City heard from dozens of stakeholders who weighed in on these proposed ADU safety regulations prior to final versions of the rules being published.

DOB agency rules include the establishment of specific technical requirements for ADUs including occupant safety, flood mitigation, water sensors, entrance identification, and exits and fire protection requirements. In addition, the rules for cellar apartments would have additional egress, window and sprinkler requirements. DEP agency rules included the creation of an updated interim flood risk area map, showing the 10-year rainfall flood risk area and the coastal flood risk area, to delineate specific flood hazard areas where subgrade ADUs would be prohibited due to the increased flood risk. DOHMH agency rules included a certification process regarding the maximum allowable levels of radon and certain organic chemical vapors found in a basement or cellar areas for the safety of occupants in proposed ADUs.

In 2024, over 2,800 building owners filled out a voluntary city survey as part of the Plus One Ancillary Dwelling Unit (ADU) Pilot Program, expressing interest in constructing an ADU on  their property. This HPD pilot program provides additional financial and technical support to homeowners looking to add an ADU.  Today’s announcement means that many of those building owners, and others around the city, can begin submitting their applications for legal ADUs, a tangible step towards strengthening their communities by building more housing in their neighborhoods.

The City is also working on standing up the pilot program authorized by Local Law 126, which will also enable the legalization of some pre-existing basement and cellar apartments that have been occupied unlawfully without prior city approval in certain areas of the city. Owners of buildings with unpermitted basement and cellar apartments that meet specific safety criteria will be able to apply for a 10-year authorization for temporary residence, as the owners work towards full legalization under these updated city regulations for ADUs. Rules for this program are forthcoming.

“We are honored to be partnering with the city as it continues to push for the creation and legalization of accessory dwelling units (“ADUs”) throughout New York City.” said Salvatore D’Avola, Executive Director of Neighborhood Restore HDFC.  “By providing these resources, the city is creating a path for homeowners interested in adding an ADU on their property.  We know that ADUs serve a dual purpose of increasing the stock of quality, affordable housing while providing supplemental income to low- and moderate-income homeowners who want to remain in their homes and communities. We applaud the city’s effort.”

“Being part of the City of Yes for Housing Opportunity is a chance to reimagine zoning not as a barrier, but as a tool for equity,” said Adam Lubinsky, Principal, WXY architecture + urban design. “For too long, the rules of the system have limited what homeowners could do with their property. NYC’s ADU for You program changes that and shows how small-scale design solutions can support intergenerational families and create opportunities for gentle growth in neighborhoods.” 

“The ADU program gives architects and planners a real seat at the table in solving New York’s housing crisis,” Chris Rice, Associate Principal, WXY architecture + urban design. “This goes beyond abstract ideas or research. This is about design that does something. By bringing the collective intelligence of people who think about space and community every day, NYC’s ADU for You program can create the housing solutions New York City needs now.” 

“We are proud to partner with the City in advancing the ADU for You program in support of homeowners and tenants across the five boroughs,” said Sabrina Lippman, CEO of Habitat for Humanity New York City and Westchester County. “Building on our successful work in Westchester, this effort to create and legalize ADUs is an important step to expand affordable housing, help homeowners stay rooted, and open doors for more New Yorkers to thrive.” 

"The City of Yes ADU program is an important step toward providing much needed housing opportunities in New York City. It allows for the creation of legal accessory dwelling units and gives homeowners more flexibility while creating meaningful opportunities for New Yorkers who have been priced out of traditional housing options," said Adam Matty, Partner at KM Associates of New York. "This initiative also provides a framework for integrating ADUs into existing properties while maintaining compliance with building and zoning requirements - transforming underutilized spaces into homes that serve both property owners and families seeking quality affordable housing. The KM Associates team is honored to provide professional guidance to this essential program."