Montgomery County, PA Outdoor Lighting: Light Trespass & Shielding (2026)

Light trespass, light from one property shining onto another, is not regulated by the county. Where a Montgomery County municipality addresses it, the rule sits in the zoning or land-development ordinance adopted under MPC Section 603(b) and typically caps the illumination (in foot-candles) measured at the property line and requires shielded, downward-directed fixtures. Not every municipality has such a standard, especially for existing single-family homes. Where no ordinance applies, an affected neighbor's remedy is a private-nuisance claim under Pennsylvania common law, which requires showing the light causes a substantial and unreasonable interference with the use of their property. Start by checking your municipality's outdoor-lighting standards.