Chicago City Wire

Mayor Brandon Johnson and Alderman Bennett Lawson have led the passage of Ordinance SO2024-0008918, which legalizes the construction of additional dwelling units (ADUs) throughout Chicago. This move is intended to address the city’s need for more affordable housing by enabling gentle increases in residential density and supporting multigenerational living.

“Today we take a critical step forward in our mission to ensure every Chicagoan has access to a decent, affordable home,” said Mayor Brandon Johnson. “By expanding ADUs to communities across the City, we are increasing housing availability and driving sustainable neighborhood investment. While this a moment to celebrate, our work is unfinished. We will continue to push for the needed reforms and community investments which will make ‘housing as a human right’ a reality for every Chicagoan. I want to thank Alderman Lawson for his unwavering leadership and commitment to this measure.”

The new ordinance expands on previous pilot programs by allowing both internal conversions—such as basement and attic units—and detached coach houses across most zoning districts in Chicago. It removes certain spacing and permitting requirements that had previously slowed down construction of such units.

"On my first day as Alderman, I introduced an ordinance to authorize ADUs citywide because I believe Chicago needs bold, creative solutions to meet our housing crisis head-on,” said Alderman Bennett Lawson. “With today’s passage of this historic policy—and with input from residents, developers, and our labor partners—we are taking real steps towards addressing our city’s housing shortage while creating good-paying jobs right here in our communities. This is a testament to our ability as members of City Council to get big things done through listening and collaboration.”

The reform makes ADUs legal by right in all non-single-family residential, business, and commercial zoning districts. In single-family residential districts, construction will be allowed in areas that choose to opt in; neighborhoods involved in the earlier pilot program are automatically included.

Once implemented, the ordinance is expected to more than double the number of parcels eligible for ADU development—from about 116,000 under the current pilot program to 245,000 parcels citywide.

The policy results from cooperation among city officials, labor organizations, and community stakeholders who used insights from the pilot phase to balance affordability goals with neighborhood preservation and workforce development needs.

To support affordability for working residents, every second ADU built on one property must be rented at an affordable rate. The Department of Housing (DOH) will also be authorized to create grant programs aimed at helping low- and moderate-income households with housing costs or assisting property owners who commit their ADUs for these tenants.

“In the midst of a national housing supply crisis, cities like Chicago must lead with smart, scalable solutions. Additional Dwelling Units are flexible and community-centered housing options that meet families where they are,” said Commissioner Lissette Castañeda. “ADUs help us create more homes without displacing residents or reshaping neighborhoods and they give homeowners the tools to build stability, support loved ones, and invest in their communities. This is how we grow housing supply with urgency and equity.”

Mayor Johnson has made affordable home construction central to his strategy for making Chicago more accessible for working people. His administration plans further reforms through initiatives such as “Cut the Tape” designed to streamline development processes across the city.