Light Trespass - How to Prevent it

You are looking to add light to a client’s outdoor basketball court or riding arena and are worried about spilling light onto a nearby neighbor’s property. Or, perhaps you are responsible for illuminating a parking lot and are concerned about casting light onto the street. Whether you’re preparing to light an outdoor basketball court, riding arena, or commercial facility, it is important to consider the effects of light trespass on your project and on any surrounding properties.

Key Takeaways

    • Definition of Light Trespass: Light trespass is unwanted spill light that affects areas outside the intended illumination zone.
    • Importance of Regulations: Many states and municipalities have specific rules to control light trespass, which must be adhered to in order to avoid fines.
    • Solutions to Prevent Light Trespass: Utilizing photometric analysis and appropriate lighting fixtures can help achieve the desired lighting levels while minimizing light trespass.

Understanding Light Trespass from the Ground Up

What is Light Trespass?

According to the Rensselaer Polytechnic Institute Lighting Research Center, “light trespass occurs when spill light is cast where it is not wanted.” Anyone who with a city- or town-owned street light outside their bedroom window has experienced the frustrations of light trespass. When light trespass is not properly handled, light can easily spill beyond your client’s property and onto neighboring land or streets where it should not. Many locations have strict regulations against light trespass, too, so the light may be both frustrating and cause for penalty.

Questions You Need to Ask to Avoid Light Trespass

Depending on your specific project, you should consider some or all of the below questions. It is important to ask these questions before installing any lights, as failure to prevent light trespass can lead to frustrated neighbors, fines from the town or city, or the costly task of replacing fixtures. These questions include:

  • What are the dimensions of the area you are trying to light?
  • To what light level (in footcandles or lux) does your area need to be lit?
  • Does your town or city specify light trespass regulations for your type of property? What are those regulations?
  • Is there a wall, fence, or any foliage on the property line that would prevent or dilute the light that reaches a neighboring property?
  • How close are your client’s neighbors? How far to the nearest sidewalk or street? How high and where, exactly, will your lights be positioned?
  • Are there shields or optical options you can add to your fixtures to better direct the light?

If you are unable to answer these questions yourself, that is okay. The lighting team at Access Fixtures is skilled in building, interpreting, and adjusting lighting solutions using something called photometric analysis. When you choose this service, our team will prepare an exhaustive report to make sure your lighting selection meets your specifications by sufficiently lighting only the areas you need to light.

What Do Light Trespass Regulations Look Like?

Not every state has regulated the levels of light trespass, and even those that have, fluctuate. Only eighteen of the fifty states, along with the District of Columbia and Puerto Rico, are currently regulating light trespass at the state level. The National Conference of State Legislatures website has a basic summary of each state and district’s regulation.

An example of such regulation from the state of New Mexico reads:

The Night Sky Protection Act regulates outdoor lighting fixtures to preserve the state’s dark sky while promoting safety, conserving energy and protecting the environment for astronomy. Requires all outdoor lighting fixtures to be shielded, except incandescent fixtures of 150 watts or less or other sources of 70 watts or less. Prohibits outdoor recreational facilities from using lighting after 11:00 p.m. Provides for a fine of up to $25 for any person, firm or corporation in violation of the law. Exceptions may apply. (N.M. Stat. Ann. §§74-12-1 et seq.)

While our lighting experts at Access Fixtures are more than happy to work with you to build the perfect outdoor lighting setup, we would recommend reviewing your state or municipal regulations (in cases where there is no state legislature) to ensure that all laws are followed to avoid penalty.

Choose a Photometric Analysis to Optimize Your Lighting Solution

All photometric reports from Access Fixtures include crucial data like average light levels, max and min light levels, 3D renderings of your area, and precise light trespass calculations. We always run our light trespass readings out to zero footcandles so our customers know exactly where their light will end. We can also provide horizontal footcandle readings at any height, factor in slope, shadows, buildings, or objects that may affect the light. If our initial design does not achieve your goals, we will make the necessary adjustments until we have a solution that does.

A simple photometric analysis will make sure you achieve appropriate light levels for your project while limiting as much light trespass as is required. If your town or city says there has to be no light trespass beyond your property line, we will make sure that happens—even down to hundreds of footcandles. Use a photometric analysis to light your project without negatively impacting your customer’s neighbors and community.

Choosing a Solution That Avoids Light Trespass

Access Fixtures is here to help you choose an appropriate, safe, energy-efficient, and durable lighting package for your residential or commercial project. Access Fixtures provides flexibility and reliability in its recommendations; we’ve provided solutions for basketball, tennis, volleyball, parking lot, and exterior lighting projects, many of which have required adherence to strict light trespass regulations.

We recently worked with a customer who needed to light a community tennis court without exceeding .15 footcandles of light trespass. Because of the speed of a tennis ball, tennis courts require significant amounts of light; preventing light trespass of .15 footcandles or greater meant abruptly halting that powerful light at the end of the court.

To achieve the two goals of adequate light levels and limited light trespass, our lighting specialists made sure to add a few factors to the photometric analysis:

  • LED luminaires that utilized forward-throw optics and shielding.
  • Conscious adjustment of pole and bracket height to better direct light where it was needed on the court.
  • Full-stop netting on the tennis court fence to act as a barrier between the court and any surrounding areas.
  • 0-10v dimming capability for all fixtures. This made it easy to increase or decrease light levels on the court, as required.

The goals and restrictions of every project are unique. Our lighting specialists lean on years of LED lighting experience to provide their recommendations, but a photometric analysis is a cost-effective way to quantify light levels in ways even the best specialists cannot.

Speak to an Access Fixtures Lighting Specialist

The decision to install lighting can be a tricky process in any scenario; light trespass adds another layer to any project. This is why our team is here to help. Not all lighting fixtures and packages are created equally, and placing one light in the wrong location or position can  create an unattractive space and further complicate things later on. Contact the lighting specialists at Access Fixtures by phone at 800-468-9925 or email us today at [email protected] to discuss your project. We are passionate about lighting and love what we do—we’ll find you a solution that works.


Whether you’re illuminating an outdoor basketball court, riding arena, or a commercial facility, it is crucial to address the potential for light trespass. Light trespass, the unwanted spill of light into areas outside the intended illumination zone, can lead to frustrated neighbors, regulatory fines, and increased project costs. To prevent these issues, thorough planning and the use of photometric analysis are essential. By asking the right questions and utilizing advanced lighting solutions like LED luminaires with proper optics and shielding, you can achieve the desired light levels while minimizing light trespass. Access Fixtures is dedicated to helping you navigate these challenges, providing tailored, energy-efficient, and compliant lighting packages

Light Trespassing Frequently Asked Questions (FAQs)

You have 590 Nanometer Amber LED Lighting questions. We have answers. If you have a question that isn’t answered below, contact an Access Fixtures lighting specialist at (800) 468-9925 or click here to visit our customer service page.

What is light trespass?

Light trespass is the unwanted spill of light that extends beyond the intended illumination zone, affecting areas outside of your property and potentially disturbing neighbors or violating local regulations.

Why is it important to prevent light trespass?

Preventing light trespass is essential to maintain good relations with neighbors, comply with local regulations, avoid fines, and ensure that light is efficiently used where it’s needed without causing unwanted glare or disturbance.

What regulations exist to control light trespass?

Many states and municipalities have specific rules to control light trespass. These regulations vary but often include limits on light levels at property lines and requirements for shielding light fixtures to direct light appropriately.

How can photometric analysis help in preventing light trespass?

Photometric analysis helps by providing a detailed report on light levels, distribution, and potential light trespass areas. It allows for precise planning and adjustment of lighting to ensure compliance with regulations and minimize unwanted spill light.

What are some solutions to prevent light trespass?

Solutions include using fixtures with proper optics and shielding, adjusting pole and bracket heights, installing barriers like fences or netting, and utilizing dimmable lighting systems to control light levels more precisely.

How can I determine if my project needs a photometric analysis?

If your project involves significant outdoor lighting and you are concerned about light trespass, a photometric analysis is recommended. It is particularly useful for projects near residential areas, roads, or other sensitive zones.

What questions should I ask before installing outdoor lighting?

Consider the dimensions of the area, required light levels, local light trespass regulations, physical barriers on the property, proximity to neighbors and streets, light positioning, and available shielding or optical options for your fixtures.

How does shielding work to reduce light trespass?

Shielding directs light downward and confines it to the intended area, preventing spill light from escaping to surrounding properties. It helps focus the illumination where it’s needed and avoids glare and light pollution.

Can I adjust existing lighting to reduce light trespass?

Yes, existing lighting can often be adjusted by adding shields, changing the angles of fixtures, lowering pole heights, or using dimmable fixtures to reduce excess light. Consulting with a lighting specialist can provide specific recommendations.

Why should I consult with a lighting specialist?

Consulting with a lighting specialist ensures that you receive expert advice tailored to your project’s unique needs. Specialists can help you navigate regulations, optimize light placement, and implement solutions to prevent light trespass effectively.