Montgomery County, MD Outdoor Lighting: Light Trespass & Shielding (2026)
Key Facts
- General limit
- 0.5 footcandles or less at lot line
- Conditional-use limit
- 0.1 footcandles near detached houses
- Fixture requirement
- Full or partial cutoff fixtures required
- Excluded municipalities
- Rockville, Gaithersburg, and 5 others exempt
- Citation
- Zoning Ordinance § 59.6.4.4.D
Summary
Montgomery County caps on-site outdoor lighting at 0.5 footcandles measured at the property line under the Zoning Ordinance, with a stricter 0.1 footcandle cap next to detached houses for approved conditional uses.
Except where otherwise stated in this Chapter, on-site illumination must be 0.5 footcandles or less at the lot line, excluding street lights within the right-of-way.
Official source re-checked September 7, 2026: no newer edition of the code had been published (publisher’s edition: 2026 S-90: Montgomery County Code contains legislation effective through May 7, 2026 | Zoning Updated Effective: April 13, 2026 | COMCOR Regulations effective as of July 1, 2026).
Full Breakdown
Montgomery County's Zoning Ordinance sets a hard ceiling on light trespass: under Section 6.4.4.D, on-site illumination must be 0.5 footcandles or less at the lot line, excluding street lights in the right-of-way. Fixtures must also be full or partial cutoff to control glare, and freestanding lights are height-capped near detached houses. For conditional uses next to a detached-house lot outside Commercial/Residential or Employment zones, the limit drops to 0.1 footcandles. The rule applies to new outdoor fixtures and fixture replacements countywide but not in Rockville, Gaithersburg, Brookeville, Poolesville, Laytonsville, Barnesville, or Washington Grove, which zone themselves.
Violations & Fines
Violations of the Zoning Ordinance are punishable as State law allows or, alternatively, by a civil fine up to the Maryland Land Use Article maximum, with each day of continued violation a separate offense.
Frequently Asked Questions
Does the 0.5 footcandle limit apply across my whole yard?
Does this rule apply inside Rockville or Gaithersburg?
Sources & Official References
Other rules in Montgomery County
Compare Montgomery County to another location·View the Maryland outdoor lighting overview
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