Occupiable spaces.
Municipal Code of Chicago § 14X-6-603.1
in effect14X-6-603.1 Occupiable spaces.
Every occupiable space must be provided with natural or mechanical ventilation.
Exceptions:
1. Natural ventilation may not be substituted for mechanical ventilation where mechanical ventilation was required by the code in effect at the time of construction or alteration.
2. A kitchen with a floor area of less than 70 square feet (6.5 m2) does not require direct natural or mechanical ventilation if there is an unobstructed opening of not less than 32 square feet (2.97 m2) between the kitchen and another room in the same dwelling unit.
Source: City of Chicago, Municipal Code of Chicago (American Legal Publishing, codelibrary.amlegal.com)URL: https://codelibrary.amlegal.com/codes/chicago/latest/chicago_il/0-0-0-2676091Fetched: 10/24/2026