Garage Conversions: Chicago vs Tinley Park
How do garage conversions rules compare between Chicago, IL and Tinley Park, IL?
Chicago has fewer restrictions than Tinley Park.
Chicago, IL
Cook County
Chicago authorizes garage conversions to coach houses (detached ADUs) and conversion units (attic/basement ADUs) under the Additional Dwelling Unit Ordinance. The pilot ordinance (effective May 2021) was made permanent and city-wide by Ordinance SO2024-0008918, which the City Council passed 46-0 on September 25, 2025, with permits accepted starting April 1, 2026. ADUs are now allowed in single-family zones within the original pilot areas plus all multifamily zones citywide (except downtown).
View full Chicago rules →Tinley Park, IL
Cook County
Converting a garage into living space in Tinley Park requires a building permit, zoning compliance, and maintenance of required off-street parking. The conversion may not create a separate dwelling unit. Required parking lost to conversion must be replaced elsewhere on the property, which is often infeasible on typical subdivision lots.
View full Tinley Park rules →Key Facts Comparison
| Fact | Chicago | Tinley Park |
|---|---|---|
| Ordinance | SO2024-0008918 (passed 9/25/2025) | - |
| Effective Citywide | April 1, 2026 | - |
| Coach House Height | 22 ft max; rear 50% of lot | - |
| Parking | No additional spaces required | - |
| Labor Standard | Reg. Apprenticeship Program (coach houses) | - |
| Permit | - | Required |
| Parking Replacement | - | Required on-site |
| Separate Unit | - | Not permitted |
| Building Code | - | Egress, insulation, detectors |
| Exterior | - | Must match dwelling |
Highlighted rows indicate differences between cities.
Chicago FAQ
Can I legally convert my Chicago garage to a coach house?
Yes, in eligible zones. As of April 1, 2026, Chicago's permanent Additional Dwelling Unit Ordinance (SO2024-0008918) allows coach houses citywide in single-family zones within the original pilot areas plus all multifamily zones (except downtown), with a 22-foot height limit in the rear 50% of the lot.
Do I need a permit to remodel or convert my Chicago garage to living space?
Yes. The Chicago Department of Buildings requires a building permit for any change of use from garage to habitable space, with plan review under Title 14X (Chicago Building Code). For ADU/coach house conversions, a pre-certification from the Department of Housing is required first.
Do I need additional parking after converting my Chicago garage?
No. The Additional Dwelling Unit Ordinance does not require additional off-street parking when adding an ADU, even when the conversion eliminates an existing garage.
Tinley Park FAQ
Can I convert my garage into a bedroom in Tinley Park?
With a building permit and replacement of required parking on the property, yes. Many Tinley Park lots cannot accommodate replacement parking, which effectively limits conversions.
Can I convert my garage into an apartment for rent?
No. Garage conversions may not create a separate dwelling unit with its own kitchen and entrance. Tinley Park does not permit ADUs in single-family zoning districts.
What happens if a garage was converted before I bought the house?
If the conversion was unpermitted, the current owner inherits the violation. Contact Community Development at (708) 444-5100 to discuss legalization options or required restoration.
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