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Legalize ADUs across Illinois, lawmaker’s bill says

Published on Feb. 20, 2020 by Steven Vance

Updated on Mar. 11, 2020

Illinois may follow in the footsteps of Oregon, Washington, and California by legalizing accessory dwelling units statewide. This would have the effect of making duplexes (two-unit houses) legal in all municipalities, creating abundant housing options. The proposed bill doesn’t let home rule municipalities opt out. High-resourced towns that prevent lower-cost housing (read: multi-family housing like apartments and condos), leading to higher housing costs and displacement of public service workers who can’t afford to live nearby, would have to participate.

A new construction coach house in Evanston, owned by a member-owner of the Evanston Development Cooperative.

Illinois Representative Robyn Gabel (18th District map) introduced House Bill 4869 last week which says that municipalities can’t have rules that explicitly or functionally ban ADUs.

Updated 2/24/20: Reps. Delia Ramirez (4th District map) and Will Guzzardi (39th District map) signed on as chief co-sponsors. Additional co-sponsors have been added: Theresa Mah (2nd), La Shawn K. Ford (8th), Carol Ammons (103rd, Urbana-Champaign)

Currently, Chicago is one of those places, disallowing ADUs through a combination of restrictive zoning standards. However, as readers of this blog know, the Chicago Departments of Housing, Planning & Development, and Buildings have been working on an ordinance to introduce to City Council.

Gabel’s district includes a fifth of Evanston, and large areas of Northbrook, Winnetka, and Northfield.

While I hoped that this was going to happen in January or two days ago, The Daily Line reported on Wednesday that introduction was delayed. Adoption of an ordinance that re-legalizes ADUs in Chicago requires broad support from our City Council members, and I don’t know if that exists yet. This map shows that eight alders have expressed their support for the needed policy change.

Most Chicago homeowners would have to obtain a zoning change to be able to build a basement unit, attic unit, or backyard house, yet ADUs are more affordable to rent and build than new construction and are a way to provide more housing options for multi-generational households and aging in place. Think of ADUs as a way for older parents to live very close to the rest of your family while maintaining their independence. Or, empty nesters can downsize into an ADU and rent out their house to a family who needs that space.

In Illinois, ADUs are allowed in Evanston and Oak Park in the form of coach houses. ADUs in other states can also be designed and built as “Junior ADUs” inside houses, attached ADUs in house additions, and detached houses (like rear houses, coach houses, and modular construction houses).

I visited a new construction coach house in Evanston earlier this month that is owned by a member of the Evanston Development Cooperative. The apartment above the garage has about 700 square feet of living space, including a single main room with kitchenette, a generously-sized bathroom, and a storage closet. The majority of space was occupied by a home office.

If you live in Gabel’s district, send her a message of support. If you don’t, email the bill to your state senator and house representative and ask if they’ll sign on as a cosponsor.


Legalize ADUs across Illinois, lawmaker’s bill says was originally published in Chicago Cityscape on Medium, where people are continuing the conversation by highlighting and responding to this story.

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