A Practice Note providing an overview of the Chicago Cooling Ordinance. The Chicago Cooling Ordinance imposes new cooling and dehumidification requirements (new cooling requirements) on certain existing residential buildings, including nursing homes, housing for older persons, licensed living facilities, and large residential buildings with a height of over 80 feet or containing over 100 dwelling or sleeping units. The Chicago Cooling Ordinance also imposes new cooling requirements on new construction designated for educational, institutional, or residential occupancy.