How Many Lumens Do I Need?

Apr 13, 12 How Many Lumens Do I Need?

If you’ve been to a home improvement store within the past 6 months, you’ve noticed household incandescent bulbs have given way to new, sometimes unfamiliar technologies. You may find a couple “full spectrum” incandescents or Halogen floodlights, but other than those, compact fluorescent and LED bulbs line the shelves. Long gone are the days of throwing your favorite brand of 60-watt light bulb in your cart and being on your way. No, you may not even be sure which funny-looking 60-watt equal light bulb you need.

Before buying a CFL or LED light bulb, get rid of any notions you have about incandescent equivalencies. How many times have you bought a 60-watt equal CFL or LED only to be disappointed by how dim it was (or blinded by how nauseatingly bright it was)? Because there is no agreed-upon standard among manufacturers for determining equivalent wattages, statements of incandescent equivalency for CFLs and LEDs are not always dependable. So to light your home the way you intend, stop thinking about watts and start thinking about lumens.

If you read our previous article on lumens, candlepower and CRI, you may remember the definition of lumens. If not, here’s the gist: “Lumens…represent the actual amount of ambient light coming from a lamp. The higher the lumens, the more ‘lit up’ a room will be.” However, while a definition of lumens is nice, if you’re like us, you’re probably asking the real question, “How many lumens do I need to light up my room?” The answer will vary based on the design and color scheme of your room, but here is good rule of thumb, loosely based on the IESNA Lighting Handbook:

Floors: 20 Lumens per Square Foot

Tables and Raised Surfaces: 30 Lumens per Square Foot

Desks and Task Lighting: 50 Lumens per Square Foot

For the average living room of 250 square feet, you’ll need 5,000 lumens as your primary light source (20 lumens x 250 square feet), equivalent to about five 100 watt incandescent light bulbs, five 23 watt CFLs, or eight 10 watt LED light bulbs. Since you probably read on your couch, you’ll also need about 4 square feet of task lighting on each end of the couch. That’s 200 lumens each (50 lumens x 4 square feet), but you’ll need more if the light source is a lamp with a shade. In your dining room, you’ll want about 30 lumens per square foot on your dining table (you want to see your food, but not examine it), so if your table is 6 x 3 feet, that’s 540 lumens.

Room Layout

Create Your Own Room Layout at FloorPlanner.com

Keep in mind, however, that these numbers are for typical conditions. If you have especially dark walls and furniture, you’ll need brighter light sources. The distance of your light source from the surface also changes the equation. We based our calculations on 8-foot ceilings and average height task lamps. Finally, personal preference will play the largest part in your decision. If you like the room to be especially bright, you may want to add 10 to 20% to our numbers. In fact, the best idea for any home may be to aim high and install dimmers to bring the light level down to where you want it.

So how much have you thought about how many lumens you need for your home? Are our numbers too high or two low? Let us know in the comments below, on our Facebook or Twitter, or even post a photo of your home on Pinterest and share it with us!

 

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8 Reasons to Use Dimmer Switches

Feb 17, 12 8 Reasons to Use Dimmer Switches

1. They save energy

When you crank down a dimmer, you are lowering the amount of power sent to a bulb. The more you dim the bulb, the less power you use, resulting in lower energy use.

2. They make bulbs last longer

As discussed in a recent blog on how to extend the life of a light bulb, delivering less power to the bulb reduces the stress on an incandescent or halogen bulb filament. The less stress the filament is under, the longer it will last.

3. They’re good for the environment

This goes back to reasons 1 & 2. Using less power means saving electricity, potentially reducing pollution produced by power plants. Longer bulb life also means throwing fewer bulbs away, resulting in less landfill clutter.

4. They’re good for your health

In addition to reducing pollution, some scientific studies suggest dimming lights in the evening has less negative effect on sleep cycles than burning bulbs at full power because dimming a bulb also lowers its color temperature, replicating the effect of the setting sun.

5. They make rooms look better

Let’s face it. Rooms with dimmed lights just look more inviting, even romantic. Next time you go to a nice restaurant, take a look at the lights. Nice aren’t they? Now go to McDonald’s. Not so nice, huh? The secret is dimming.

6. They make you look better

You may be a pretty girl or a handsome guy, but that doesn’t mean lighting can’t still help. When you dim a bulb, you are changing the light from bright white to a warm, inviting tone, softening the appearance of your hair and skin.

7. They’re easy to install

Contrary to what you may think, most dimmers are incredibly easy to install. Just turn off the power at your breaker, remove your standard toggle switch, and replace it with your new dimmer. The same 3 wires you disconnected from your toggle switch (positive, negative, and ground) attach to the dimmer in the same configuration.

8. They’re cheap

This may be the best reason of all. While sophisticated, multi-location electronic dimmers like the Lutron Maestro can cost upwards of $25, a standard rotary dimmer or slide dimmer will cost less than $10.  For less than a $10 investment, what do you have to lose?

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Understanding Life Hours, Part 3: How to Extend the Life of Your Bulbs

Jan 27, 12 Understanding Life Hours, Part 3: How to Extend the Life of Your Bulbs

The third and final part in a series about life hours and how you can use this spec to inform your purchase and maximize the life of your bulbs.

If you’re a lighting nerd like most of us at 1000Bulbs.com, you’ve likely heard of the 110-year-old Centennial Bulb in Livermore, California. If (more likely) you’re not a lighting nerd, here’s the brief rundown: The Centennial Bulb was installed in a firehouse over 110 years ago and still hasn’t burned out. It’s not known exactly how it has lasted so long, but there are a few good clues: One, it has only rarely been moved; two, it has been switched off only a handful of times, and three, it is operated at very low power.

The two previous articles in this series explained how manufacturers determine life hours and how life hours and warranties are two different things. This third and final article in the series explains how you can make your light bulbs last longer. We can’t guarantee they’ll last 110 years (in fact, we can almost guarantee they won’t), but by following a few tips you can easily double or triple the life of your bulb. One caveat, however, because not all light bulbs use the same technology, these tips do not apply to all bulbs.

Don’t move it! Light bulbs get hot. Really hot. And when metal (which makes up a bulb’s filament) gets hot, it gets brittle. The more you handle a bulb with a brittle filament, the more vibration you subject it to, making the filament much more likely to snap. This doesn’t apply only to handling the bulb; it also applies to placement. Any bulb installed in a place that moves also moves. The swish of a ceiling fan or the slam of a refrigerator door, while barely heard by you, is a light bulb’s death knell. It’s for this reason that you may have seen special bulbs with reinforced filaments marketed as “ceiling fan bulbs” and “appliance bulbs.” As you might have picked up, this rule only applies to bulbs with filaments, like incandescent and halogen bulbs.

Leave it on! This may sound contradictory to common sense, but it’s not. Every time you flip a switch, you are blasting your light bulb with power. That poor little filament is forced to go from room temperature to 5000° F in a fraction of a second! You do that too many times, and the filament will literally crack under the pressure. This also goes for ballasted bulbs like linear fluorescents, CFLs, and HID lamps. In the case of an instant start fluorescent ballast, you’re hitting the fluorescent tube cathodes with 600 volts every time you flip the switch. After so many power cycles, the lamp will fail. Keep in mind, however, that while this trick will prolong the life of your bulb, it could also increase your electricity usage.

Operate it at low power. This may be the real secret to the Centennial Bulb’s longevity. Less power means less heat, which translates to less stress on a bulb filament. If you live in the United States, your house is operating on ~110V, so if you buy a bulb rated for 130V, you’ll be hitting the bulb with 15% less power than it is designed to handle  (130V – 15% = 110.5V). You can stretch this principle even further with a dimmer switch. When you dim a bulb, you are lowering the voltage delivered to the bulb filament, putting it under less stress. This also applies to fluorescent technology, but in a slightly different way: Unlike an instant start ballast, a programmed start ballast supplies a much lower starting voltage and heat to the lamp.  If you switch to this type of ballast, you could extend the life of your fluorescent bulbs by over 30%.

Finally, remember that the aim of extending bulb life, in most cases, is to save money. Is it really worth it to make that incandescent bulb last forever by dimming it and leaving it on for longer periods? In many cases, it’s better to switch to a more efficient CFL or LED. But if you’re a die-hard incandescent fan, or want to recreate your own Centennial Bulb, these tips will come in handy.

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Using Halogens and Light Dimmers as a CFL Alternative

Want to save energy but don’t like CFL light bulbs? You’re not alone. CFLs are among the most efficient, commercially available lighting sources, yet these bulbs aggravate many homeowners and business operators. Despite technological improvements, some still complain that CFLs do not dim well, flicker, or cast an unappealing light. Fortunately, those who find themselves among those who do not like CFLs have an alternative in halogen light bulbs.

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