How to add a wireless 3-way light switch: I recently built a house and because of a last minute electrical circuit change, we ended up with a Leviton decora light switch in the kitchen that did nothing. I also had some kitchen island lights that were only controlled at one end of the kitchen by a simple two way switch. I wanted a way to use this unused light switch to control the kitchen island in a 3 way switch configuration WITHOUT a traveler between the 2 switch boxes.
After searching a very long time, I found many solutions that were less than optimal. My secondary goal was to maintain the same look as a standard “dumb” decora switch like this one. Most wireless smart switches either added a bunch of lights, dimmer sliders, or other visual features that make the switch stand-out when it is in a box with other “dumb” switches.
If I had a traveler 3-way wire between the boxes, there are many options to turn that circuit into a “smart” switch (example: tp-link Kasa Wi-Fi 3-way switch), but the key about my situation is that I needed to do this without a traveler wire.
A simple description of what we need to do: 2-way switch continues to control light circuit while also switching the circuit from a remote “virtual switch” location.
Original Decora Switch Look and Function Using Hubitat
I found a way using the $100+ wireless smart hub Hubitat. If you have been doing Home Automation (also known as “HA”), you’ve probably come across Hubitat or other alternatives like SmartThings (a Samsung product) or Home Assistant (there are many others) to automate actions in your house like thermostats, wireless cameras, plugs, motion sensors, etc…
Hubitat has a few pros that work great for me:
- Supports multiple wireless technologies like Z-wave, Zigbee, and other wifi devices
- Z-wave is the preferred technology because it doesn’t run on the same channels as 2.4ghz WiFi AND the devices can create a mesh network to extend your Z-wave network reach
- HUGE community support
- Works without internet – most alternatives require their manufacturer’s cloud connectivity to function (think internet access and manufacturer keeping service active)
I’ll detail more about how I did it below, but I wanted to also touch on a method WITHOUT a hub:
Wireless 3-Way Light Switch WITHOUT a Hub
If you don’t want do do this without a Home Automation hub, you get a little more limited on your options. Lutron makes a ~$70 switch kit called Caseta and Pico P-PKG1WB-WH with options for Dimmer. There is also the more simple Lutron Caseta Switch P-PKG1WS with less buttons to just turn the light On and Off. It is a 110v wall switch and battery remote combo that is a stand-alone system (no hub required). You can place the remote in any location and make it look like a hard-wired switch by putting it in a standard electrical box or using double-sided tape and their faceplate.
I did potentially find alternatives, but they were usually unreliable, no longer made, devices were too large to fit into a standard electrical box, or much more expensive.
Wireless 3-Way Light Switch and Remote Virtual BATTERY Switch WITH a Hub
In this scenario, you have a working 2-way switch and you want to add a switch in a location WITHOUT power. If you have a Z-wave compatible hub, a great option is the Zooz 700 Series Z-wave ZEN34 switch. This switch is similar to the Lutron Pico remote mentioned above as it can be installed in an existing box, or double-sided tape to the wall with a permanent look using the faceplate.
Based on some people’s use, the battery lasted many years. These are good options for a z-wave remote as they are the cheapest switches I could find at around $25 depending on your source.
- A typical z-wave switch like the Zooz Z-wave S2 ZEN26 switch – Usually around $30.
- A miniature z-wave or zigbee relay behind the “dumb” switch. See next section for how those work
Using the Zooz ZEN26 switch is similar to a standard decora light switch, but with 2 minor differences that might change your opinion if you want to maintain a similar look and feel to your other decora switches:
- There is a LED light below the switch
- It is a rocker switch so that it always returns to the middle position after pressing up or down
Hypothetically, you can also do a “direct association” between z-wave devices so that you no longer need a hub, but you do need a hub to originally program them. Using the battery powered ZEN34 switch and 110v powered ZEN26, you’re looking at around $55.
Wireless 3-Way Light Switch WITH a Hub
This is the option I chose. In this scenario, you need 2 switch boxes with power and without a traveler wire between the two; one of the switches needs to control the target circuit. You can do it with mini relays or switches.
I opted to use the Sonoff ZBMINI relay because they are much cheaper ($10-15 each) and they install in the electrical box behind the “dumb” wall switch. This option was completed for $25 for BOTH switches. I was able to use existing “dumb” switches to give a uniform look to other switches (ex: no lights) in the box AND the switch is still operates in the up/down position instead of returning to the middle position after rocking up/down.
You could also use two standard smart switches (like the Zooz ZEN26 mentioned above) instead of relays that fit into the box. This options is $60+ as you need to buy 2 switches.
You do have other options for smart relays that use other wireless technologies besides the Zigbee ZBMINI’s mentioned above. They do cost double or more:
- ENERWAVE Z-Wave relay – $43
- Shelly WiFi Relay – $15/each (2-pack for $30) – google for documentation to get working with Hubitat. Many people like these as they are UL listed, thus perceived as safer
- Zooz Z-wave Relay ZEN51 – $24+shipping
Installing and Connecting Z-wave or Zigbee Devices for Wireless 3-way Light Switch – Hubitat
After following the manufacturer wiring instructions, the devices (smart switch or smart relay) should automatically enter pairing mode. I recommend only connecting one device at a time so it is easily identifiable. These instructions use screenshots from the Hubitat, but the steps should be similar if you are using a different home automation hub.
Add Devices to Hubitat
Open you Hubitat interface by going to its IP address in the browser (can also be found at https://portal.hubitat.com/findmyhub). Navigate to “Devices” on the left-hand side.
In the top-right, click “Discover Devices” and choose the wireless technology you are connecting to. In my case, I was using the ZBMINI that communicates over Zigbee. Once you choose your wireless technology, a button will appear that says something like Start “pairing” or “inclusion.” Once your device is found, give it a name that clearly identifies what it is.
After you pair the device, you need to tell Hubitat what type of device it is. Using the device type of “Generic” will usually work fine. In my case, because the ZBMINI is a Zigbee device, I choose “Generic Zigbee Switch”. Both switches need to be setup as a Switch, not a Virtual Switch.
Create Rule in Rule Machine
After both switches are added as devices in Hubitat, you need to create a rule for the Built-in App “Rule Machine”. Click “Apps” from left menu and then “Add Built-in App” in the top-right. Search for “Rule Machine” and choose it.
Create a name for this new rule and choose “Select Trigger Events.”
Under “Select capability for new Trigger Event” choose “Switch”
Then select the device that is NOT connected to the circuit you want to control.
Choose *changed* from “Switch turns” dropdown and “Done with this Trigger Event”. Then on the next page (not shown), choose “Done with Trigger Events”
You should be back on the main page for the rule you are creating. Choose “Select Actions to Run.”
Select the “Control Switches” and “Toggle switches”
Select the device that controls the 2-way lights and “Update”. Select “Done with this action”. On the next page (not shown), select “Done with Actions”.
Select “Done.” Your new rule in Rule Machine should be completed. You can test the lights and see if it works. I noticed I had to flip both switches a couple times to get everything reacting properly.
– If you think you made a mistake, you can delete the rule and start over. Go to the Apps page and click the Gear Icon next to the rule name. Scroll to the bottom and choose “Remove this child instance of Rule-4.0”.
– The original 2-way switch location should work even if the hubitat is not turned on. However, the virtual switch you setup will not work unless the hubitat is turned on.
– I noticed an almost instant light turn on when using the location of the 2-way switch and about 0.5 seconds when using the virtual switch location. Both were very acceptable response times.