ADU Ordinances Comparison
September 12, 2025
Compared to alternatives, Alderperson Lawson's ordinance (SO2024-0008918, introduced in May 2023) to legalize Accessory Dwelling Units (ADUs) across Chicago will build more homes at lower costs, create more jobs, give homeowners more choice in how they build an ADU, and lessen the city's housing shortage.
Update on 9/23/2025: A compromise ordinance between Alders. Lawson and Quinn was reached and some parts of this comparison may be outdated.
Rents in Chicago are growing faster than the country’s average, and the research consensus says that adding more homes slows down how fast rents increase; in some cases more housing can decrease the rents compared to the present day. A decoy ordinance was recently introduced by Ald. Quinn; if adopted it would block homeowners from building new ADUs or allowing the rental of their pre-ADU (finished basements with separate entrances common in bungalows) to a neighbor.
The housing shortage is a citywide problem that requires a citywide solution, but the decoy ordinance will severely curtail ADUs' benefits for families and communities by adding costs and barriers that Chicagoans of color will be unable to overcome.
Comparing Ald. Lawson's original ordinance and Ald. Quinn's last-minute ordinance
Ald. Lawson's Ordinance — Ald. Quinn's “Decoy” Ordinance
Costs for Homeowners
1 — Lower costs
Homeowners will have the freedom to choose from any of licensed contractors who meet their needs, ensuring they can select the lowest cost and most qualified bid. — Higher costs
Homeowners will be restricted to finding and choosing only those contractors which participate in a Registered Apprenticeship Program, decreasing choice, adding red tape, and increasing construction costs. Alderpersons cannot opt out of this.
Labor Requirements
2 — Same as any other house
Like building any single-family house, two-flat, or other construction, homeowners and other property owners can choose from any contractor and subcontractor licensed in the City of Chicago. — Digresses from typical construction
Regarding the Registered Apprenticeship Programs requirement, there is no publicly accessible list of construction companies that are participating.
These programs are also not inclusive nor representative. Statistics of apprenticeship participants in the Illinois construction industry, according to the U.S. Department of Labor: 76% are White, 11% are Black, and less than 1% are Asian; 24% identified as Latino (of any race). Only 11% are women.
Additional Standards
3 — Minimal and predictable standards
1 permit per block per year allowed in RS-1 zoning districts.2 permits per block per year allowed in RS-2 zoning districts.3 permits per block per year allowed in RS-3 zoning districts.Owner occupancy required for owners of detached houses. — Unbounded standards may be imposed
Each eligible area would be allowed to have "any reasonable conditions [emphasis added] for the allowance of conversion units, including, but not limited [emphasis added] to the number of conversion units, and, if applicable, coach houses, may be established within such area generally, or that may be established per block within such area."
Eligible areas will also have to have owner occupancy requirements defined.
