Polk County, IA Outdoor Lighting: Dark Sky Rules (2026)
Key Facts
- No-cutoff fixture, residential
- 0.20 fc, 10 ft max height
- 90-degree cutoff, LI/HI district
- 1.50 fc, 35 ft max height
- Under-90-degree cutoff, LI/HI
- 4.00 fc, 50 ft max height
- Property line cap near homes
- 0.2 footcandles, all fixture types
- Sports field exemption cap
- 80 ft post height, Board of Adjustment
Summary
Polk County's zoning ordinance requires every exterior light fixture to use one of three defined cutoff types and caps illumination and pole height for each, from 0.20 footcandles and 10 feet for unshielded residential fixtures up to 4.0 footcandles and 50 feet for fully shielded industrial lighting.
Exterior lighting shall be a No cutoff, Total cutoff up to ninety (90) degrees, or total cutoff of light at an angle less than ninety (90) degrees. The lighting shall meet the standards set for each type of fixture. ... (A) No Cutoff light fixture ... When a light source or luminary has no cutoff (see illustration below), the maximum permitted illumination and the maximum permitted luminary height shall be: ... (2) Lighting on uses adjacent to residential zoning districts shall not exceed .2 footcandles at the property line. This requirement shall also apply to residential properties adjacent to residential properties. ... (C) Total cutoff of light at an angle less than ninety (90) degrees light fixture ... When a luminary has total cutoff of light at an angle less than ninety (90) degrees (see illustration below) and is located so that the bare light bulb, lamp, or light source is completely shielded from the direct view of an observer five (5) feet above the ground at the point where the cutoff angle intersects the ground, then the maximum permitted illumination and the maximum permitted height of the luminary shall be: ... All nonresidential in AG, AT,ER,RR 1.00 25 ft.
Official source re-checked September 7, 2026: the cited page had not changed since it was quoted.
Full Breakdown
Article 12, Division 1, Section 4 of the Polk County Zoning Ordinance, Exterior Lighting Options, requires every fixture to fall into one of three defined categories: no cutoff, total cutoff up to ninety degrees, or total cutoff at an angle less than ninety degrees, each meeting a separate table of standards. 30 footcandles and 20 feet in the Light and Heavy Industrial districts. 50 footcandles and 35 feet for nonresidential uses in Light and Heavy Industrial districts. 00 footcandles and 50 feet in Light and Heavy Industrial districts, because the design keeps the light source itself invisible off-site. 2 footcandles at the property line. 2 footcandles or less.
Violations & Fines
A fixture that exceeds its cutoff category's footcandle or height limit, or that is installed without the required exterior lighting plan for non-residential development, is a violation of Article 12 enforced through Article 23. The Zoning Administrator issues a written Notice of Violation with a correction deadline, escalating to a citation, a stop-work order, and civil penalties assessed per day the fixture remains out of compliance.
Frequently Asked Questions
What kinds of outdoor light fixtures does Polk County allow?
How tall can a shielded parking lot light be in an industrial district?
Do ball fields and tennis courts have to follow the same lighting caps?
Is there still a light limit at my property line if my neighbor uses a fully shielded fixture?
Sources & Official References
Other rules in Polk County
Compare Polk County to another location·View the Iowa outdoor lighting overview
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