Cook County, IL Outdoor Lighting: Dark Sky Rules (2026)
Key Facts
- Max light at property line
- 0.1 footcandle at 60 inches
- Scope
- County Departments only, not private property
- Adopted
- Ord. No. 12-O-12, Feb. 15, 2012
- Efficiency target
- Lamps should exceed 72 lumens per watt
- Exempt lighting
- Special events, seasonal decor, construction, aircraft
Summary
Cook County's Lighting Ordinance directs County Departments to shield outdoor fixtures on County-owned roads, buildings and properties, capping light spilling onto neighboring lots at 0.1 footcandle. It binds County facilities only: private homes and businesses in Cook County are not covered.
Purpose. The purpose of the Cook County Lighting Ordinance is to achieve effective and efficient lighting, while:...(4)Allowing visual access to starry night skies....(d)Applicability. The requirements of this Code shall apply to all new and replacement lighting on roadways, developments, properties, buildings or structures under the jurisdiction of Cook County Departments.
Full Breakdown
Adopted in 2012 as the 'Cook County Lighting Ordinance' (Sec. 2-341 through 2-343), the rule directs County Departments to shield and aim outdoor fixtures on County roadways, buildings and properties so light at any property line, measured 60 inches above grade, stays under 0.1 footcandle. Upward-directed lighting must be eliminated where practicable, nonessential lighting must be shut off after hours, and lamps should exceed 72 lumens per watt. Exceptions cover state/federal-mandated lighting, special events, seasonal decorations, construction and aircraft-control lighting. The ordinance governs only lighting under County Department jurisdiction: it does not regulate lighting on private residential or commercial property anywhere in Cook County, incorporated or unincorporated.
Violations & Fines
No fines apply to residents or businesses: the ordinance binds County Departments internally; noncompliant County lighting projects can be flagged through the President's Office or County Board oversight, not code enforcement.
Frequently Asked Questions
Does Cook County require homeowners to shield outdoor lights to reduce light pollution?
What light level limit applies to County-owned outdoor lighting?
Is Chicago covered by this ordinance?
Sources & Official References
Other rules in Cook County
Compare Cook County to another location·View the Illinois outdoor lighting overview
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