Do you trespass on your neighbors? You might not physically, but it’s all too easy to trespass with lighting in this day and age.

My neighbors aren’t the types to stand in their yard and go about watering their plants while sending half of the water over the fence and onto my hamburger (granted I usually eat veggie burgers, but that’s not relevant here).

At night, however, my neighbors seem to forget about the fence and show little hesitation in showering my yard, my house, and even the inside of my house with half of the light they use to see. I love my neighbors, but I hate their porch lights. Good thing the glass is clear, because I’m sure our light bulbs would not be bright enough to push through a frosted shade (that’s sarcasm). Candles might have needed every ounce of help they could get, but electric light is not nearly so wimpy.

To be fair, my twinkling lights twinkle right across the property line into their living room window as well. Good neighbors, indeed.

What is Light Trespass?

None of them, thankfully, think it is acceptable behavior to walk through my yard after sunset, crack open my bedroom window, and hang their leg inside my window. Hey, that wouldn’t be too bad, right? Just a leg?

And I do not creep over to their homes at night, crack open their windows, and stick a leg or arm into their home. That would be trespassing on private property, and I could get arrested (or worse).

But we seem to show no hesitation in letting our light creep over to our neighbors’ homes and sneak into every window of the house. Every single night.

This is called light trespassing and is even illegal in some jurisdictions.

Why Light Trespass is Bad

There are a lot of reasons as to why light trespass is bad. Just one example: you are paying for every single photon you sling at your neighbors. You are spending money (and wasting electricity), but you are also harming your neighbors’ health and wellbeing.

Sleeping with even a little bit of light could harm heart health. Light trespassing into our homes at night keeps our bodies from the deep sleep needed to reset our circadian rhythms, regulate our blood sugar, and recharge for the next day. We could study the science all day, but the results are straightforward: light at night is bad.

How to Avoid Light Trespass in Installations

The solution is not that difficult: stop shining light across property lines. However, there are additional ways you can be more mindful of your clients’ neighbors.

Try searching for Dark Sky-friendly light fixtures or “full cutoff” fixtures that point all the light down and carefully conceal the bulb behind shields and shades. Guess what? You will end up spreading more light onto your clients’ porch, patio, deck, and yard as a bonus.

Sure, you can use a security light to make yourself feel safer, but studies show this is not necessarily as beneficial as we hoped. So, skip the glare-bomb security lights and use barn-style lights. Instead of blinding your client, you will illuminate their house so neighbors can see the criminal trying to pry open their window. Win-win.

But the best light at night — when no one is in your yard or on the front porch — is no light. Turn it off. Your neighbors (and your wallet) will thank you.

David Warfel is Chief Evangelist of Light at design firm Light Can Help You.

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