King County, WA Outdoor Lighting: Dark Sky Rules (2026)
Key Facts
- Fixture requirement
- Fully shielded, no direct uplight
- Property-line cap
- 1 foot-candle maximum
- Parking lot fixture height
- 15 feet maximum
- Geographic scope
- North Highline/White Center subarea only
- Citation
- King County Code § 21A.09.100
Summary
In the North Highline/White Center design-standards area of unincorporated King County, new and substantially improved buildings must minimize night-sky illumination and use fully shielded fixtures that block all direct uplight.
A. Lighting design shall promote public safety, encourage visibility throughout the entire site, consider a mature landscape, and minimize light spillover to adjacent properties and illumination of the night sky.
B. All public areas shall be illuminated at the following levels:
1. Building entries shall have up to three foot-candles;
2. Sidewalks and walkways shall have between one-half foot-candle and one-and-one-half foot-candles; and
3. Parking areas shall have between one-quarter and three-quarters foot-candles.
C. Lighting shall be provided at consistent levels. The lighting uniformity ratio shall not exceed ten-to-one as determined by the minimum lighting level in relation to the average lighting level in a specified area.
D. All building lights shall be directed onto the building itself or the ground immediately adjoining the building. Illumination at the property line shall be a maximum of one foot-candle.
E. Parking lot lighting fixtures shall be nonglare and mounted no more than fifteen feet above the ground.
F. All lighting fixtures shall be fully shielded, where a solid barrier at the top of the fixture in which the bulb is located blocks all direct uplight. (Ord. 19881 § 184, 2024: Ord. 19687 § 15, 2023. Formerly K.C.C. 21A.60.070).
Full Breakdown
King County's urban design standards for the North Highline subarea (the unincorporated area around White Center) require new and substantially improved buildings to minimize light spillover and illumination of the night sky. Every fixture must be fully shielded so a solid barrier blocks all direct uplight, parking lot fixtures may not exceed 15 feet in height, illumination at the property line is capped at one foot-candle, and the lighting uniformity ratio cannot exceed ten-to-one. The rule applies only within the mapped North Highline design-standards area, not countywide, and never in Seattle, Burien, or other cities that run their own codes.
Violations & Fines
Site plans and building permits in the North Highline design area are reviewed by King County's Department of Local Services for shielded fixtures before approval; unshielded lighting can hold up permit issuance and site-plan sign-off.
Frequently Asked Questions
Does this dark-sky rule apply across all of unincorporated King County?
What counts as a fully shielded fixture here?
Sources & Official References
Other rules in King County
Compare King County to another location·View the Washington outdoor lighting overview
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