Back To Basics: DIY 3-Way Lights
Da Ya Think I’m Sexy?
With apologies to Rod Stewart, this time I am not writing about cool new gadgets or control systems. I’m going back to basics to describe one of the most common smart home projects.
This solves a real problem and is easy to implement. A great starter DIY first project or a nice add-on to your existing home automation.
What is a 3-Way Light?
By definition, a 3-way light, is where you have more than one switch controlling a light. The typical example is a hallway or staircase where you want to be able to control the light from either end of the hallway or from either floor of the staircase.
Electricians have solved this problem for years using a wiring scheme involving a third wire, often called a traveller, which runs between two light switches connected to the same light fixture.
If you have two switches that control one light, then you have a 3-way light installation. Note that this is completely different from older 3-way bulbs.
Usually installed in a table or desk lamp, a 3-way bulb has two filaments inside and special wiring in the bulb base and the light bulb socket giving you three different light levels.
Most 3-way bulbs have been phased out with the wider use of dimmers and modern LED lighting, but many are still installed.
Trivia tip: Because of the unique wiring in 3-way lights, you cannot rely on “On” being “Up” and “Off” being “Down” on the switch paddle.
Depending upon how each switch was last used, “On” can be either “Up” or “Down”. Moving the switch to the alternate position will turn the light on or off, but it can be a little annoying.
Quick tip: The 3-Way wiring can be extended to support more than two switches. It is very common to have 3, 4, or even more switches controlling one light. So it would be more accurate to call it “N-Way lighting control”, but I’ll stick with 3-way for simplicity.
Where There’s a Will, There’s A Way
As homeowners, we are faced with two common situations: We have an existing 3-way setup in a hallway or stairs and we want to automate the lights preserving the 3-way operation or we want add 3-way control to a regular light that has only one switch.
In the first scenario, the goal is simple — make sure we add smart home lighting control as a convenience and improvement without losing the marvelously simple, yet valuable, 3-way control.
This can be easier said than done. Some of the simpler consumer oriented smart light switches do not support 3-way lighting control.
This is especially true if you use a general-purpose on/off smart switch (not a dimmer) because you decided you don’t use or need dimming and/or the cost of the switch is cheaper than one that includes dimmer features.
Don’t even get me started about the problems with smart light bulbs (where the control circuity is inside the base of the bulb). If you want a refresher, you can read my critique here: Are Your Smart Bulbs Making Your Smart Home Dumb?
Take it from me, never add smart home automation to lights if it removes basic 3-way use. Keeping the rest of the family happy by not taking away a basic feature they have been accustomed to using is extremely important.
The second scenario, adding 3-way control, is a great DIY starter project. Just identify an area of your home where you would like the convenience of controlling a light from more than one physical location. Here’s some ideas besides hallways and stairs:
Workshop attached to a garage — You may enter from either the garage or an outside door.
Backyard or outdoor lights — You have several doors that open to the same yard or patio.
Large rooms — Just like hallways, larger rooms may be entered from different sides or directions
Bedside lamp — Who wants to get out of bed to turn out the lights?
“There’s an app for that”
Before we talk hardware, I need to address the elephant in the room — smart home apps. It should be obvious that we can all achieve the effect of a 3-way switch by using an app on our smartphone as an extra switch.
With our light connected to a smart home hardware dimmer or switch, we can control it from anywhere just using an app. Walking upstairs or down the end of the hall and want to turn off the light when there is no physical switch? No problem, just use the app on your phone and switch it off.
That is certainly a reasonable approach. For some situations where you would like to have 3-way control but simply cannot justify the cost of extra hardware, using an app might be ideal.
But in most homes, having to dig our smartphone out of our pocket to turn off a light just doesn’t make sense! Do you have your phone with you when you are in your pajamas raiding the fridge at 2:00 am?
Do your 5-year old children even have their own smartphones yet? What about house guests? You get the picture. It is too limiting and far too inconvenient to insist on using an app all the time.
The same is true for voice control. I love using my Amazon Alexa’s and I know Google Home or Apple Siri can also do the job. But there are times when voice control is inconvenient so you need an alternative.
Many otherwise good DIY lighting controls do not have a built-in solution for 3-way light switches. The products were only designed to control a single light and they perform that function fine.
Fortunately, there is a workaround than provides a decent solution. The idea is to use a wireless switch to simulate 3-Way control. A battery operated switch press is detected by the home automation system which then controls the actual light.
The wireless switch has no direct wired connect to the light. It can be placed anywhere or moved around as needed.
There are now a good selection of battery operated switches available in a choice of technologies and physical options. Switches are available that use Bluetooth, Wi-Fi, Z-Wave, Zigbee or manufacturer proprietary communication protocols.
Software support varies with some switches working with multiple control systems, others created for a specific company’s own products or a single automation system. If a switch does not directly support your lighting system, you may be able to use a 3rd party integration solution like IFTTT or Stringify to link everything together (but that does loop the communications through a cloud server).
Physical designs also vary with a choice of colors, shapes and mounting options. Some switches are designed to be cute and modern, like the Fibaro big red button or the Logitech large circular button.
The most versatile approach is to make the switch the same size and shape as an actual typical wall mounted switch or dimmer. With the appropriate mounting bracket, these switches can be installed right next to existing switches or replace them.
Any of these switches are a good solution for converting a single light into a 3-way system. The wireless switches can be mounted on the wall or placed on a table anywhere — there is no need for electrical wiring or modifications.
The disadvantage of this approach is that the additional switches will not work if your automation system is not working. There is no “fall back” operation as a basic light switch.
Don’t forget aesthetics — With strange designs that look more like toys or gadgets, some of these switches may not win the support of everyone in your household. Switches should be obvious, easy to use, and not look different just because “under the hood” they work differently.
3-Way Done Right!
For proper 3-way lighting control, until recently we would have had to venture into the much higher-priced world of larger traditional home automation systems. Lighting controls from established companies such as Lutron, Control4, Savant, and Crestron support proper 3-way switching, but at a high price.
For the savvy consumer/prosumer, Lutron’s Radio RA2 Select, a smaller, more affordable version of commercial Radio RA2 lighting system fully supports 3-way (and N-way) lighting controls.
In addition to the expected in-wall dimmers, Lutron has a remote dimmer in-wall module which works with the special wiring already installed for 3-way switches. This makes replacing existing 3-way dumb light switches with 3-way smart switches straightforward and cost effective.
GE, a well-known traditional electrical/appliance company, also provides a remote switch that works with their smart switches for true 3-way operation. The GE Add-On Switch will work with any GE Smart Lighting switches that use Bluetooth, Zigbee, or Z-wave.
iDevices is another company that provides 3-way support. This is a more expensive solution as you need two of their switches and they have to be paired to each other via Bluetooth.
I haven’t worked with iDevices products yet, but they support Amazon Alexa, Apple HomeKit, and Google Home Assistant so if you need a product to work with all of these control systems this might be another choice to consider.
Insteon is another company that has in-wall switches and dimmers with support for 3-way lighting. You simply purchase two of them and install them where needed. Although they don’t have a less expensive remote switch version like Lutron does, the Insteon switches do not need a special Bluetooth connection like iDevices.
Solutions For 3-Way Lighting Control
In summary, there are two approaches for DIY / consumer projects to have 3-way lighting controls: Use a wireless switch with smart home automation programming to simulate 3-way operation or use a true 3-way enabled in-wall switch/dimmer from companies like Lutron, GE, iDevices, Insteon, or others.
Now when planning your lighting control system, you can accommodate the desire for 3-way switches and not have to give up this important capability or rely only on a software/app workaround.
Are you going to add 3-way lighting controls to your smart home? Let me know what you think.
Robert E. Spivack, Smart Home Technology Specialist.
I design, install, & retrofit home automation solutions at www.DoItForMe.Solutions