LED lighting for homes is the best method for interior home lighting today. While LED lights are not inexpensive, the long lifetimes and low power use mitigate the initial high cost. Still, navigating the myriad choices of LED lighting, on top of the choices that exist today for interior lighting, can confuse and intimidate.
I’m not talking about just replacing existing Edison-style, incandescent bulbs with LED equivalents. If all you’re looking for is a replacement for ordinary light bulbs, we already have you covered. Instead, we’ll cut a broader swath, looking at LED interior lighting in a more general way. During our extensive kitchen remodeling project, I spoke with several contractors and lighting sales people about the current state of LED lighting. Both the underlying technology and interior lighting products have evolved rapidly in the past few years. That rapid evolution, however, has also generated huge confusion.
One thing is clear: compact fluorescent lighting is now a transitional technology. Fluorescents will always have a place, but CF-style lighting is starting to fade away, gradually being replaced by LED-based products.
Before we talk about lighting in particular, let’s talk about a related topic, a critically important one for many homeowners: color.
The Problem of Color
Anyone shopping for a PC monitor, particular for photo or video editing, understands the importance of color temperature and color gamut. But most of us often forget that these measurements are also important when shopping for lighting. Unlike monitors, the standard often used is Color Rendering Index, or CRI, which indicates how a particular light source will reproduce the colors of objects in the environment faithfully.
Most of us have experienced the eerie look of sodium lamps, often used in outdoor lighting. Colors of objects within the range of the light often take an unsettling reddish cast. High pressure sodium lights have a CRI of roughly 25 (on a scale of 0-100), which gives you an idea of why objects don’t look right in areas using sodium lights as the primary light source. (The other issue is that the emission spectrum of high pressure sodium lamps is shifted towards red.)
Two different lights can have identical CRI ratings, but objects would look different if the emitted light from the two sources are rated at different color temperatures.
Most consumer interior lights have CRI ratings ranging from 60-100. However, the CRI isn’t the only thing to worry about. The color temperature, which is a way to gauge the emission spectrum of the light, is also important. Two different lights can have identical CRI ratings, but objects would look different if the emitted light from the two sources are rated at different color temperatures.
Color temperature is a measurement of the color output by a light source, usually displayed as degrees Kelvin. The problem is that most people are used to the color temperature of standard incandescent bulbs for interior lighting, which is roughly 2700K. Incandescent bulbs at this color temperature are often labeled “warm white”, although you’ll find a few bulbs labeled “cool white” or “daylight”. Those are often 5000 – 5600K bulbs. “Warm” and “cool” are misnomers in a sense, since the actual color temperatures of “warm white” represent the light created by black bodies at cooler temperatures than the light emanating from black bodies at higher temperatures.
Most people are much more comfortable with 2700 – 3000K, and feel the whiter light with more blue content is harsher, even though 5000K is closer to the roughly 5600K of daylight color. So when you go shopping for LED lighting, look for either “warm white” on the box or a color temperature rating of 2700-3000K.
In some cases, though, people don’t necessarily notice differences in color temperature. I’ll touch on that shortly.
Low Power Use Drives New Installation
In our neck of the woods (Silicon Valley), any new kitchen project that requires remodeling also requires reduced power lighting. So we went with CREE LED recessed lights as the main ceiling lights.
However, the under-counter lighting uses low voltage LED strips. These are, surprisingly enough, roughly 5000K – bright white. Yet no one in our household has complained. That’s probably because it’s indirect, and reflects off the cherry veneer of the cabinets. The power converters are hidden between cabinets.
We also had a 300W halogen light fixture hanging over the dining room table, which was replaced by a new fixture consisting of three 12W LED lamps, which look to be somewhere around 2700K to 3000K. They also look pretty sharp.
But what do you do with existing light fixtures, particularly when you’ve installed new fixtures which may clash with the old?
Years before our major kitchen remodel, I had the house rewired, running coax and CAT5e cabling throughout the house. As part of that, we also had recessed lighting fixtures with Edison sockets installed, including the family room (which houses the HDTV and A/V rack) and living room – 20 in all. We used R40 style compact fluorescent floods in those fixtures. At the time (roughly 2007), it required some effort to find R40 CF bulbs which also happened to be 2700K. Each flood was 14.5W apiece.
When the kitchen was remodeled, the recessed lighting in the dining room looked out of place after the entire project was done.
The answer turned out to be a CREE LR6 retrofit kit. The look in the dining room now looks very similar, though perhaps not identical, to the dedicated recessed fixtures in the kitchen. These CR6 retrofit kits use slightly less power than the CF floods they replaced – about 12W versus 13.5W – but the savings is minimal. On the other hand, if you’re replacing a number of 50-65W can lights with these kits, the energy savings can ramp up quickly.
The LR6 lights also rated at a 90+ CRI rating, which is pretty good for LEDs.
The Family Room Retrofit
Meanwhile, the family room is where the HDTV lives. I’ve always been irked by the lack of a dimmer. The existing CF lights were eventually replaced by non-dimmable LED lights, but they still were the old style light fixtures. So I decided it was time to install retrofit CREE LR6s along with LED-capable dimmers. I also wanted to correct a mistake one installer made years ago, where the double light switch was reversed: the front switch turned on the rear five lights and the rear switch, the front three lights.
The real trick is finding LED capable dimmers. The good news is that a number of companies now manufacture LED capable dimmers. They’re not hard to find – but you do need to read the package labeling. After all, you’d never pick up a PCI graphics card to install in a PCI Express slot, right? The same holds true here: make sure the tech you install is complementary to the other technology you want it to work with.
When you unpack the switches, they look a little different than normal light switches. For one thing, the body of the light is completely encased, concealing the electronics inside to manage voltage settings for LED lighting. There are also no terminals to connect your interior switch wiring; the switches are pre-wired.
Step 1: Turn Off Power!
Before you take on an interior wiring job, you want to go to your breaker box and either switch off or remove the circuit breaker to the lighting in the room which is being upgraded. Working with a live 110-120V, 20A circuit while trying to attach a switch is extremely dangerous. Test to make sure that power is disabled, by either trying to turn on the light, or using a voltmeter.
If all you’re doing is installing the retrofit kit, then turning off power may seem pointless. But since you’ll be tugging on a wired Edison socket at one point, turning off power to the room is still a good idea. Do it.
Step 2: Prep The Fixture
You turned off the power to the room, right? If not, go do that now.
The interior of my particular recessed fixture houses the Edison socket and a bracket to set the correct height for the floodlight. Also attached are trim pieces: a plastic cone and surround for the light.
The retrofit kit includes a Cree LR6 light assembly mated to an Edison socket adapter. It also includes three stiff leaf springs to hold the light in place at whatever height is needed, as well as permanently attached trim.
After the original trim and bracket are removed, you pull down the socket a bit – as far as the wiring will allow. Then you screw in the Cree LR6 assembly. The instructions suggest rotating the leaf springs to their outermost setting before attaching the assembly to the socket, but I found it a little easier to rotate the springs after the light was screwed in.
Once attached, just push the entire assembly gently into the can until the built-in trim is flush with the ceiling.
Step 3: Install The Switch
The old switch actually consisted of a pair of single-pole switches controlling two sets of lights in the room, installed behind a dual-switch plate.
If you’re uncomfortable with working with your home wiring, hire an electrician to wire the switch for you. I’m not showing photos of my particular installation, because it’s old enough that the wiring is all the same color, except for the bare ground. I was able to match up the wiring correctly by adding bits of tape with labels to ensure I didn’t reverse wire anything.
The Lutron dimmers were also pre-wired for three-way lighting, but this was just a single-pole application, so the extra wiring was capped off. This time around, I also oriented the two switches correctly, so the front switch manages the front set of lights.
I still have a couple of halogen fixtures in the house, as well as a number of CF bulbs. I’m not replacing all of them at once, but I can foresee a time when the entire house will be lit with LEDs. LED technology for interior lighting has come a vast distance in just a few years, so there’s still a lot of outdated information floating around the web.
However, if you take some care when buying LED fixtures and bulbs, it’s not that difficult. Understanding the basics including a barebones understanding of color temperature and CRI, and you’ll be in good shape. If you want dimmers, or three-way lighting, you’ll also likely need to change out your switches. Once you do, you won’t have to worry about your lights for a very, very long time.