Lake County, IL Outdoor Lighting: Dark Sky Rules (2026)
Key Facts
- Applies to
- Unincorporated Lake County only
- Residential-abutting limit
- 0.5 footcandle at property line
- Nonresidential-abutting limit
- 1.0 footcandle at property line
- Shielding
- All luminaires must be shielded
- Exempt
- Single-family homes, public streetlights
Summary
Unincorporated Lake County caps outdoor light spillover at 0.5 footcandle on residential-abutting property lines and requires all luminaires to be shielded against glare.
Outdoor lighting shall not exceed one-half footcandle at any point on the adjoining property if the subject property abuts a residential zoning district or a lot containing a residential use ... All luminaires shall be shielded to prevent light and glare spillover to adjacent residential property and abutting rights-of-way
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: 2026 S-15: Supplement contains: Local legislation current through Ord. 26-0618, passed 6-9-2026 | State legislation current through ILCS Pamphlet 2025 #5).
Full Breakdown
Lake County's Unified Development Ordinance regulates outdoor lighting on new development in unincorporated Lake County (single-family detached houses and public streetlights are exempt). Under § 151.168, light spilling onto an adjoining residential-zoned or residential-use property cannot exceed one-half footcandle, measured at the property line; the limit rises to one footcandle where the adjoining land is nonresidential. Every luminaire must be shielded to keep light and glare off adjacent residential land and rights-of-way, and flickering, flashing, search, laser, and mercury-vapor lights are banned outright. This applies only in the unincorporated county. Waukegan, Highland Park, Gurnee, Libertyville and Lake County's many other municipalities set their own outdoor-lighting standards.
Violations & Fines
Planning, Building and Development Department enforces through the site-development permit process; noncompliant lighting plans are rejected, and installed fixtures exceeding the footcandle limits or lacking required shielding must be corrected as a zoning violation.
Frequently Asked Questions
Does this lighting rule apply inside Waukegan or Gurnee?
Is my house's porch light regulated?
Are mercury-vapor security lights allowed?
Sources & Official References
Other rules in Lake County
Compare Lake County to another location·View the Illinois outdoor lighting overview
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