Chicago ADU Pilot Ordinance — 5 Zones, Coach House, Basement Conversion
Chicago ADU reality. ADU Pilot Ordinance 2021 limited to 5 geographic zones (Northwest, Northeast, Southwest, Southeast, West). Coach house reconstruction vs basement conversion, CDOB Standard Plan, historic preservation consultation. $140K-$380K typical.
Chicago's ADU Pilot Ordinance (2021) permits accessory dwelling units in five geographic pilot zones: Northwest, Northeast, Southwest, Southeast, and West. Outside those zones, ADUs remain prohibited. The pilot covers two distinct types: (1) coach houses — detached rear structures, new construction or reconstruction of demolished coach houses, and (2) conversion units — basement or attic conversions in existing 1-4 unit buildings.
AskBaily routes Chicago ADU projects to one BACP-registered GC with pilot-zone experience. The pilot is under periodic review for citywide expansion.
What a Chicago ADU filing involves
- Pilot zone verification — check parcel against pilot map.
- Coach house vs conversion unit selection.
- CDOB Standard Plan Review — 12-26 weeks.
- Historic Preservation Office consultation if in landmark district.
- BACP GC + IL State Plumbing + Chicago Electrical.
- Chicago winterization R-values on any new exterior envelope.
Frequently asked questions
Can I build an ADU anywhere in Chicago? No — only within the five pilot zones (Northwest, Northeast, Southwest, Southeast, West). Outside, ADUs are prohibited.
What is a coach house? A detached rear structure, historically used for carriages or servants' quarters. Chicago's pilot permits new coach houses and reconstruction of demolished coach houses on qualifying parcels.
How much does a Chicago ADU cost? New coach house: $240K-$450K. Basement conversion: $140K-$280K. Attic conversion: $180K-$320K.
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Each neighborhood has distinct regulatory posture. Baily pre-scopes against the specific overlay your home sits under.
- Lincoln ParkChicago Department of Buildings
- Old TownChicago Department of Buildings
- Gold CoastChicago Department of Buildings
- StreetervilleChicago Department of Buildings
- River NorthChicago Department of Buildings
- LakeviewChicago Department of Buildings
- WrigleyvilleChicago Department of Buildings
- North CenterChicago Department of Buildings
- Roscoe VillageChicago Department of Buildings
- UptownChicago Department of Buildings
- AndersonvilleChicago Department of Buildings
- EdgewaterChicago Department of Buildings
- Rogers ParkChicago Department of Buildings
- RavenswoodChicago Department of Buildings
- Lincoln SquareChicago Department of Buildings
- Albany ParkChicago Department of Buildings
- Irving ParkChicago Department of Buildings
- AvondaleChicago Department of Buildings
- Logan SquareChicago Department of Buildings
- BucktownChicago Department of Buildings
- Wicker ParkChicago Department of Buildings
- Ukrainian VillageChicago Department of Buildings
- Humboldt ParkChicago Department of Buildings
- Portage ParkChicago Department of Buildings
- Jefferson ParkChicago Department of Buildings
- Norwood ParkChicago Department of Buildings
- Edison ParkChicago Department of Buildings
- DunningChicago Department of Buildings
- Belmont CraginChicago Department of Buildings
- The LoopChicago Department of Buildings
- West LoopChicago Department of Buildings
- Fulton MarketChicago Department of Buildings
- South LoopChicago Department of Buildings
- Near North SideChicago Department of Buildings
- Little ItalyChicago Department of Buildings
- University VillageChicago Department of Buildings
- PilsenChicago Department of Buildings
- Little VillageChicago Department of Buildings
- East Garfield ParkChicago Department of Buildings
- West Garfield ParkChicago Department of Buildings
- AustinChicago Department of Buildings
- LawndaleChicago Department of Buildings
- ChinatownChicago Department of Buildings
- BridgeportChicago Department of Buildings
- Back of the YardsChicago Department of Buildings
- McKinley ParkChicago Department of Buildings
- Brighton ParkChicago Department of Buildings
- EnglewoodChicago Department of Buildings
- Hyde ParkChicago Department of Buildings
- KenwoodChicago Department of Buildings
- BronzevilleChicago Department of Buildings
- South ShoreChicago Department of Buildings
- ChathamChicago Department of Buildings
- PullmanChicago Department of Buildings
- BeverlyChicago Department of Buildings
- Morgan ParkChicago Department of Buildings
- Mount GreenwoodChicago Department of Buildings
- HegewischChicago Department of Buildings
- South ChicagoChicago Department of Buildings
- East SideChicago Department of Buildings
- Oak ParkChicago Department of Buildings
- EvanstonChicago Department of Buildings
Talk to Baily about your Chicago project
Start a scoping conversation. Baily verifies every matched contractor against the specific licensing, insurance, and permit requirements that apply in Chicago before you get a quote.
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