Now that the 2016 Energy Code has gone into effect in California, this is a good time to review the new lighting requirements, as well as your lighting options.
Changes to the Code
The revised code reduces energy usage throughout the home, but it also provides a much more straightforward set of guidelines. The earlier code, issued in 2013, was rather complicated, with different rules for different rooms of the house. For example, we had to use a formula to determine how many incandescent fixtures could be installed in a kitchen. To meet the code, we would install ugly fluorescent fixtures over a beautiful new kitchen island, and then, after final inspection, the owners would change out those fixtures for the incandescent pendant lights they really wanted in the first place.
Now, all permanently installed fixtures in a home must be high-efficacy, the reality being that all light sources will have to be fluorescent or LED. But that doesn’t mean you have to buy fluorescent or LED fixtures. You CAN use fixtures that take screw-base bulbs, as long as you use high efficacy bulbs that are labeled JA8-2016. The one place we can no longer use screw-in bulbs is recessed lighting; all recessed cans must be high-efficacy fixtures.
Another important new change to the code is that all fixtures must be controlled by a dimmer switch, or, alternatively, they must have a switch that turns the fixture off when the room is vacant; these switches are called “manual-on/automatic-off vacancy sensors.” The only exceptions to this rule are hallway and closet lights, which do not require either a dimmer or a vacancy sensor switch.
The code gets a little stricter for bathrooms, laundry rooms, utility rooms, and garages. In each of these spaces, at least one fixture must be controlled by a vacancy sensor switch. Presumably, people are more likely to use these rooms briefly and then wander away without switching off the lights.
Exterior lighting is also under stricter regulation. Outdoor lights must have a photocell and a motion sensor, or a photocell and astronomical time switch for dusk to dawn lighting.
For residential lighting, we typically use three types of bulbs—which, by the way, are correctly called “lamps.” Today’s residential light fixtures use incandescent, fluorescent, and LED lamps.
Incandescent lamps are becoming a thing of the past, although some diehards still have hidden stashes in their basements. These lights use a lot of energy, and they create a substantial amount of heat. But we love the warm color they produce, and the ambiance provided by dimming.
Fluorescent lamps are much more energy efficient, but they have many drawbacks. They can flicker, they’re slow to warm up to their full brightness, and most of them can’t be dimmed. The industry claims that CFLs will last for ten years, but the reality is they only last for a year or two because turning them off and on drastically shortens their lifespan.
LED lamps more energy efficient than CFLs, they’re dimmable, and they have good color rendering. The bulbs are more expensive than CFLs, but cost has dropped to a point where this is no longer an excuse for not buying them.
Watts and Lumens
Watts are a measure how much energy is being used. Lumens are a measure of how much light is being produced. Knowing how many lumens per watt a lamp produces tells us the efficacy of the lamp.
A brand new 60-watt incandescent bulb produces about 800 lumens of light. As the bulb ages, it will produce less light, but it will keep using 60 watts of energy. A halogen bulb, which is a more efficient type of incandescent bulb, will produce 800 lumens using about 43 watts.
That same amount of illuminance, 800 lumens, will be produced by a 13-watt CFL or a 10-watt LED lamp. The energy savings are significant.
Color Temperature and CRI
The color temperature of light is measured in degrees Kelvin. Confusingly, the higher the temperature, the cooler the color appears. Candlelight has a color of about 2000K, while daylight is 5000K or higher.
Incandescent light has a temperature of 2700K, which appears as a yellowish, warm color. As these bulbs age, they not only produce fewer lumens, they also glow at a warmer color. Dimming incandescent lights produces the same effect—as they dim, the color temperature shifts lower and the color becomes warmer.
Today, both fluorescent and LED bulbs are available in many color temperatures. Look for 2700K if you want to mimic incandescent light. Often, boxes of bulbs will be labeled “warm white” or “soft white,” but close examination will show that the bulbs’ color is 3000K. This may not be what you want. And remember, as the Kelvin temperature increases, the color of the light will be cooler.
There is one more measurement of a light source—the CRI, or Color Rendering Index. This number tells us how accurate a light source is at rendering color. The higher the CRI, the better its color rendering ability. A CRI of 90 or higher is excellent, and this is the standard that is now required for residential lighting in the new Energy Code.