Municipal Code of Chicago § 14X-6-601.1 Scope.
14X-6-601.1 Scope.
This chapter provides minimum standards for natural and artificial light and natural and mechanical ventilation in existing structures.
LIGHT AND VENTILATION
Municipal Code of Chicago tit. 14X, ch. 14X-6
in effectMunicipal Code of Chicago § 14X-6-602.1 Occupiable spaces.
14X-6-602.1 Occupiable spaces.
Every occupiable space must be provided with natural or artificial light sufficient to permit the maintenance of sanitary conditions and the safe occupancy of the space and utilization of the appliances, equipment, and fixtures.
Municipal Code of Chicago § 14X-6-602.2 Habitable spaces.
14X-6-602.2 Habitable spaces.
Every habitable space in a dwelling unit or sleeping unit and every regular classroom in a Group E occupancy must have at least one window facing directly to the outdoors or to a court. The total glazed area of exterior windows for each habitable space must equal or exceed 6 percent of the floor area of the room or space. Where walls or other portions of a structure face a window at a horizontal distance of less than 30 inches (762 mm) and extend to a level above the ceiling of the room, that window may not be included in calculating the total glazed area.
Exceptions:
1. Kitchens.
2. Where a room or space has an unobstructed or glazed opening to an adjoining room equal to or exceeding 8 percent of the floor area of the room and the adjoining room has exterior windows providing a total glazed area equal to or exceeding 8 percent of the combined floor area of both rooms.
3. Habitable spaces which comply with the requirement for natural light in effect at the time of construction or rehabilitation.
(Amend Coun. J. 2-19-20, p. 14473, Art. V, § 35)
Municipal Code of Chicago § 14X-6-602.3 Common corridors and stairways.
14X-6-602.3 Common corridors and stairways.
Every common corridor and stairway in residential occupancies, other than within a dwelling unit, must be adequately lighted at all times when the building is occupied, either by natural or artificial illumination.
Exception: In a Group R-5 occupancy, an adequate lighting system which may be turned on when needed by conveniently located light switches may be provided instead of a full-time lighting system.
(Amend Coun. J. 2-19-20, p. 14473, Art. V, § 36)
Municipal Code of Chicago § 14X-6-602.4 Emergency system.
14X-6-602.4 Emergency system.
Where applicable, an emergency illumination system must be provided in accordance with Article 700 of the Chicago Electrical Code.
Municipal Code of Chicago § 14X-6-603.1 Occupiable spaces.
14X-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.
Municipal Code of Chicago § 14X-6-603.2 Habitable spaces.
14X-6-603.2 Habitable spaces.
Every habitable space in a dwelling unit or sleeping unit, other than a kitchen, must have not less than one openable exterior window. The total openable area of the window in every room must be not less than one-third of the minimum glazed area required by Section 14X-6-603.1.
Exceptions:
1. Where a room has an unobstructed or operable opening to an adjoining room equal to or exceeding 8 percent of the floor area of the interior room, but not less than 25 square feet (2.33 m2), and the adjoining room has exterior windows providing a total openable area equal to or exceeding 4 percent of the combined floor area of both rooms.
2. Conditions allowed by the Chicago Building Code in new construction.
Municipal Code of Chicago § 14X-6-603.3 Bathrooms and toilet rooms.
14X-6-603.3 Bathrooms and toilet rooms.
Every bathroom and toilet room must be provided with any combination of the following:
1. An operable window with an openable area equal to or exceeding four percent of the floor area.
2. Mechanical ventilation complying with Chapter 14X-8.
3. A gravity vent flue constructed with noncombustible materials leading to the roof of the building and providing an aggregate clear area equal to or exceeding five percent of the floor area of the room, but not less than 120 square inches (0.08 m2). Gravity vents must be provided with a weather cap, directional vane, or rotary type ventilation above the roof level.
Municipal Code of Chicago § 14X-6-603.4 Process ventilation.
14X-6-603.4 Process ventilation.
Where injurious, toxic, irritating, or noxious fumes, gasses, dusts, or mists are generated, a local exhaust ventilation system must be provided to remove the contaminating agent at the source. Contaminated air must be exhausted to the exterior and not recirculated to any space.
Municipal Code of Chicago § 14X-6-603.5 Clothes dryer exhaust.
14X-6-603.5 Clothes dryer exhaust.
Clothes dryer exhaust systems must be independent of all other ventilation systems and must be exhausted outside the building in accordance with the manufacturer’s instructions.
Exception: Listed and labeled condensing (ductless) clothes dryers.
Source: City of Chicago, Municipal Code of Chicago (American Legal Publishing, codelibrary.amlegal.com)URL: https://codelibrary.amlegal.com/codes/chicago/latest/chicago_il/0-0-0-2676067Fetched: 10/24/2026