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Dim Some, Lose Some

Waste extends far beyond what winds up in the landfill. The International Dark-Sky Association leads the charge against light pollution.

dim some

You see them everywhere: stadium-quality floodlights as bright as the sun, controlled by an overly sensitive motion detector, installed on an outside corner of a house ostensibly to overilluminate a 10-by-10-foot patch of yard (while also shining into the neighbor’s bedroom). The lights are sold to frightened homeowners as security measures, but they’re wasteful, intrusive, and, according to Bob Parks, director of the International Dark-Sky Association (IDA), might actually make the house less safe.

The IDA was originally established to combat light pollution, excessive artificial light that destroys our ability to enjoy the night sky. But it quickly came to realize that management of light outside the home was equally important to the quality of life inside the home. “The point of effective lighting,” Parks explains, “is to use only the light you need, when you need it, and to shield it so the light doesn’t go where it’s not wanted.” In the past few decades too many people, fearful of shadows near their home, have done their best to install lighting fixtures anywhere they can. Complaint letters in IDA’s files show that far too many new houses and housing developments are willing to forego energy efficiency and neighborly courtesy for the false security of nonstop glare.

And the ironic thing is that using light that’s too bright, while sold as a security measure, actually may make the situation more dangerous. “Inside your house you might have an appropriate level of lighting,” says Parks. “When you go outside and are hit with bright floodlights, you may be temporarily blinded. Your eyes try to adjust to the new glare, and you lose your ability to see into the shadows. And then you’re a brightly lit target for anyone hiding there.”

Parks recommends that when planning a lighting system, homeowners should ask themselves these questions: Do I actually need to light that area? If so, how much light is enough without overlighting and causing a glare? And do I need that light all the time? 

  • intro to lighting

    An Introduction to Lighting

    One of the oldest proclamations in Western literature—maybe the very oldest, depending on how you see things—is “Let there be light.” And for most of human history, whether we dwelled in caves or in Gilded Age mansions, light was inseparable from heat: Domestic lighting consisted of either letting sunlight inside or burning something organic. The Egyptians were making candles from beeswax and animal fat 5,000 years ago, and except for the discovery of new fuel sources—whale oil, ahoy!—the candle continued to illuminate homes deep into the 19th century. is your online home in the modern world. Join us as we follow our team around the globe on Twitter, Facebook, and Pinterest. Want more? Never miss another word of Dwell with our free iTunes app.


Also, how inviting is the lighting? My mom's former mobile home park used to have nice pole lights, about 6 feet tall - a 100W bulb, or a 20W florescent bulb, put out a nice inviting yellow light through the lens of the fixture.
Later, the park went with lights that were the height of regular street lights, which put on an awful light that made the colors of homes and landscape look awful - and showed every minute flaw in a home. When florescent bulbs were put into these fixtures, the light was much better, but still not as inviting as the old fashioned 6 foot pole lamps. Also, many of the street-light sized fixtures put light where you didn't need it - you could read a newspaper on top of the roof - but you had awful shadows down below, where you really needed the light.
What struck me was that a standard 100W light bulb would have been a better lighting value - putting the light where you needed it, using the 6 foot pole lights - or, replace the light bulb with a 20W or less florescent bulb, and you have a lot of light, where you needed it - and the place looked very warm and inviting to come home too.

A pet peeve of mine. I live in the country, and I love the night sky, but too much of the skyline is dominated by people who feel they have to flood their yards with lights. Some of this is farmers, protecting their equipment, but not all of it. I long ago learned that bright lights destroys your night vision, so all you do with the floodlights is limit your vision to the area of the lighting.