Master electrician Heath Eastman enlightens Kevin O’Connor on LED light bulbs. Heath explains how these modern bulbs are more efficient, how to choose one to match an old school incandescent output, and more. Heath even shows Kevin how the temperature scale works, and points out that not all LED bulbs are compatible with certain fixtures and switches.
Advantages of LED Bulbs
LED bulbs are the newest iteration for common household light bulbs, and there’s a lot to like about them. Between improved energy-efficiency, longer lifespans, color flexibility, and lower heat output, these bulbs are lightyears ahead of the incandescents of old.
Pro Tip: Ray Johnston, a staff scientist at 3M, explains that LED bulbs have “heat sinks”—fins or another way out for the heat generated when energy passes through the semiconductors—”which help them use much less wattage and emit much less heat than incandescent bulbs do.” However, LEDs are more sensitive to their surrounding temperature and need adequate airflow to work well. Overheating won’t make a bulb explode, but it will shorten its life—so check whether your LED bulb is rated for use in enclosed fixtures or capped recessed lights before installing.
The efficiency gains of LEDs over incandescents are dramatic. As demonstrated on a This Old House segment, LED bulbs use as little as 10% of the electricity of an equivalent incandescent lamp—meaning a 65-watt incandescent can be replaced by an LED drawing only about 10 watts, roughly 80% less electricity. And while LEDs may cost more upfront, their longevity—lasting 5, 10, 15 years or sometimes longer depending on usage—means they more than pay for themselves over time.
Importance of Light Bulbs Equivalency
When choosing an LED bulb, homeowners and DIYers need to think a little bit differently than simple wattages. When replacing a 60W incandescent bulb, shoppers will find bulbs that draw far less wattage but offer equivalent lighting output. In these cases, it’s helpful to refer to the package which should clearly state the incandescent wattage equivalency and the actual wattage (often around 10 percent of an incandescent).
It’s also important to take lumens into consideration. Lumens describe the actual visible light that a bulb will emit, and this value will be on clear display on the LED bulb’s box, as well.
As explained in a This Old House segment on LED basics, an 800-lumen bulb is equivalent to a 60-watt incandescent light bulb—but different types of light bulbs use much more or much less power to produce the same amount of lumens. That’s where wattage comes in: wattage is the power consumed, not the brightness of the light.
LED Light Bulb: Color and Temperature
When shopping for LEDs, look for the Lighting Facts label on the package—it posts the Kelvin (K) rating right on it. As This Old House Magazine noted in its guide to demystifying LEDs: “The closer to the lower end of 2700K, the warmer the light (yes, that does sound backward).” That label is the quickest way to ensure you’re getting the right color temperature before you buy.
LED bulb colors come in terms of temperatures. In most homes, these colors will land on the Kelvin temperature scale between 2700K and 5000K. The lower the temperature, the warmer and more yellow the light will appear. The higher end of the scale will trend toward bright white, even becoming blue over the 5000K mark. For living rooms, the lower end of the scale is best, and for garages, look for the higher end.
There are even fixtures that will allow the homeowner to choose the color. These LED light fixtures install in the ceiling and feature a sliding switch that changes the temperature of each light.
Sizes and Shapes of LED Light Bulbs
While the compact fluorescent bulbs typically look like pigs’ tails or curly fries, LED bulbs look like regular bulbs. They have standard shapes and even come in a variety of base sizes for any fixture. From candelabra bases to outdoor settings, there is an LED bulb for any fixture.
What to consider before installing
If an LED bulb will be attached to a circuit on a dimmer switch, there are two things to note. It’s important to ensure the bulb is a dimmable LED, and that the switch itself is rated for LED bulbs. If not, the bulbs might flicker or won’t last as long.
Also, while LED bulbs run much cooler than incandescents, it’s still important to ensure that the bulb is rated for an enclosed fixture. For glass bulbs on ceiling lights, or even fixtures that only mostly enclose the bulb, it’s important to check the package.
Resources
Heath explains that the energy efficient, go-to choice in lightbulbs are the light-emitting diodes or LED bulbs. LEDs can produce the same amount of light as an incandescent bulb while using a fraction of the energy.
Unlike incandescent bulbs, with LED bulbs you have the option to choose the color temperature of the light. This is measured by a Kelvin scale where lower numbers mean yellow candlelight and higher numbers mean blue daylight.
Heath explains there many different shaped bulbs, but two common shapes/bases homeowners will be dealing with are the A19 medium base and B12 Candelabra bulbs. Heath also discusses how to read lightbulb labeling to identify enclosed fixture ratings as well as wattage and lumens.
Pro Tip: When shopping for LED bulbs, don’t overlook the Color Rendering Index (CRI). As explained in This Old House Magazine, bulbs are rated for their ability to render color accurately using the CRI scale, where incandescents score a perfect 100. Any bulb with a CRI of 80 to 90 suits all but the most discerning eyes and will let you see colors accurately. You may need to check the manufacturer’s website for the CRI rating; despite all that small print on the package, it’s not always listed there.
