Alongside representatives from CMAP, Community Investment Corporation and Preservation Compact, ULI Chicago, and the Chicago Association of Realtors, I also spoke at a subject matter hearing on June 11, 2024, to the Chicago City Council’s zoning committee about the necessity to expand accessory dwelling units to be allowed citywide. Read more about the proposed ordinance.

Hello, my name is Steven Vance. I am an urban planner and consultant in Chicago. I am also a member of Urban Environmentalists Illinois. I have been studying, promoting, and collaborating around ADUs for six years. I was on ULI Chicago’s task force, have presented to various groups about building an ADU, and created a free directory on ChicagoCityscape.com that lists local architects and companies who can design and build ADUs. 

1st Ward Alderperson La Spata comments on the proposed ADU expansion ordinance during the subject matter hearing.

Given that background of some of my ADU work I feel that I understand a lot of how the adoption of ADUs in the last three years has fared and can point out future benefits that the city will gain if the proposed ordinance is adopted. I will highlight some of those future benefits.

Removing the maximum coach house size cap. The proposed ordinance would change the cap on how much floor area a coach house could have. Allowing larger coach houses on larger lots will allow more family-sized units with two or more bedrooms. Additionally, larger coach houses can make them more cost effective to build, because of the high fixed costs in building a coach house of any size. The proposed ordinance could facilitate more family-sized coach houses than are currently being built.

Allowing ground level coach houses through the administrative adjustment for parking. The proposed ordinance would allow property owners to build a coach house at grade, meaning it can be accessible. This would make it easier for families to decide to build a small house for an aging family member, who may very well be the current owner, as well as put a dent in the dearth of accessible housing. A second benefit of this change is that ground level construction is significantly cheaper than building atop a garage.

Allowing all-residential buildings in non-residential zones to participate. The proposed ordinance would allow thousands of residential-only buildings that are in B and C zoning districts to add an ADU. The Institute for Housing Studies at DePaul University found that 25 percent of buildings with 5 or more units fit into this category but are currently ineligible. These are the building sizes that are most capable of adding two or more ADUs. If two or more ADUs are built, half must be rented affordably. Adopting this ordinance means those buildings would be able to add ADUs.

Allowing coach house and conversion units on the same lot can also be cost effective for property owners. Either one would likely require a water service or electric service upgrade so it makes sense to make one upgrade to serve multiple new homes.

I believe that the biggest gains in the city’s ADU policy will come from allowing them citywide, in all residential and mixed-use zoning districts. Citywide expansion makes it simpler for the departments to administer, makes all buildings capable of adding an ADU eligible to add an ADU, makes it easier for homeowners to add an additional home to fit their changing household needs, and lets other property owners add to the city’s housing abundance thereby slowing down rent increases that the city is experiencing.


Note: The plan, as explained in Crain’s and the Chicago Tribune, is to vote on the ordinance at the June 25, 2024, zoning committee meeting, and if approved there the City Council would vote at their July meeting. (City Council does not meet in August.)