Gaithersburg, MD Outdoor Lighting: Dark Sky Rules (2026)

Gaithersburg addresses outdoor lighting through Chapter 24 (Zoning) of its Code of Ordinances and through the site plan review process for new development. Commercial, institutional, and multi-family projects must submit a photometric plan showing fixture types, mounting heights, illumination levels, and light trespass at property boundaries. Fixtures must be fully shielded (full-cutoff type) to direct light downward and prevent upward glare. Maximum illumination at the property line is typically limited to 0.5 footcandles to protect adjacent residential properties. Parking lot lighting must provide adequate safety illumination without excessive brightness. Montgomery County lighting standards under the County Code Chapter 59 (Zoning) also apply and require compatibility with surrounding uses. Residential properties are not required to submit lighting plans, but outdoor lights that create a nuisance through excessive brightness, glare, or light trespass may be subject to code enforcement complaints. HOA communities such as Kentlands and Lakelands often have architectural guidelines specifying approved fixture styles, wattage limits, and placement requirements. Contact Gaithersburg Planning at 301-258-6330 for development lighting standards.