Call them home automation standards, languages, or protocols…Z-Wave and Zigbee, like Wifi, and Bluetooth are communications standards. I have smart home gear using all four.
If you are going to have Z-Wave or Zigbee compatible devices, remember first, you still need, very reliable Wifi. Without the Wifi element, your Z-Wave or Zigbee hubs/bridges, have no way to talk to your phones, tablets, computers, and watches.
Z-Wave and Zigbee are mesh systems – which is generally a wonderful thing. What that means is each device hooked up is a relay for all commands. That’s very different from Wifi, where every device has to be in range of a central “hub” – your Wifi Router.
In other words, the more Z-Wave devices in your home, the more reliable your Z-Wave. Ditto for Zigbee.
Z-Wave is perhaps the stronger standard between the two “Z’s”. I believe it originated long ago for the home environment. It likely originated with security products – smart locks, alarms, and also outlets, and is still especially strong there. But today, there are Z-Wave devices in almost all aspects of home automation. Z-Wave, if I understand this correctly, is a “controlled” standard (licensed from the founding company.), rather than an open standard such as Zigbee (or Wifi…), ruled by independent standards committees. There are positives and negatives to each approach, in this regard. Z-Wave is known for tight standards, while Zigbee reminds me a bit of the Android operating system, which is open (even if Google controlled), in that a phone manufacturer can modify the Android code to meet their needs and features, but that also means a higher likelihood that some devices will have features or capabilities that others can’t support, preventing proper operation.
Zigbee has the advantage of being open, which means members of the Zigbee alliance (hundreds of companies), can add to the standard (through standards committees I assume). Open standards are more flexible, tend to evolve faster. This advantage is, I suspect partially offset by a higher likelihood of some devices not working with others, because some will have enhancements the other decided not to support. Hey, nothing’s perfect, right?
No matter, the bigger differences is in how they work, and even more importantly, what you can do with each. So let’s start with Z-Wave, primarily because I have far more Z-Wave devices in use in our dream home, and can therefore pontificate better.
Z-Wave and Z-Wave Hubs
Consider Z-Wave devices:
I have many Z-Wave devices installed in our “Dream Home.” These all work through a Z-Wave hub like my (Samsung) SmartThings, or the Wink hub or one of the many others out there…(I previously used a Nexia, and before that, a HomeSeer Z-Wave Hub.)
A list of the Z-Wave compatible devices here (to date) includes door locks (Schlage and Kwikset at the moment), outlets and dimmers: GE, Linear, Eve, Aeon Labs…. I have Z-wave light bulbs, including Zipato, window and door sensors, Fire alarms and water leak sensors too, that are all Z-Wave
These do not have their own Apps, rather they are controlled by the App of the Z-Wave Hub. That is very important to remember!
As you can see in the menu shots, the SmartThings App controls lots of devices. Mind you, not all are Z-Wave, but may of them are, and for those, the Hub’s App is the only control you have.
Other devices on my menus, such as LIFX, are other types, (LIFX bulbs, for example are Wifi, so I can control them via the SmartThings App, or using LIFX’es own App.
Here’s the rub with Z-Wave – because you are dependent on your Hub’s app to run Z-Wave devices, you can be very disappointed if the Hub’s app is doing a lousy job of supporting the particular devices you want to integrate!
Here’s an example of what I mean. With the Nexia Z-Wave Hub, the app didn’t allow me to control the color of the Zipato color bulbs, so they became dimmable white bulbs. By comparison, my SmartThings App does support color on the Zipato, but strangely doesn’t really support the bulb doing white. (Btw in both cases, these hubs have a community of users, mostly DIY types and installers, who provide extra capability that can be downloaded.
The bulb is an RGBW so you would normally use the white LED when you want white output, but instead, the SmartThings tells the bulb to do white using R, G, and B. Well folks that’s a poor alternative. Color bulbs are going mostly RGBW now, because the whites have always been the weak spot with RGB only bulbs. In the case of the Nexia, the community provided a minimal solution, I could log onto the Nexia Hub’s website (not the app, remember they charge a monthly fee), and there I could select colors from RGB sliders. Sadly, whatever color selected, effectively turned the bulb into that color light. If I select blue green, that’s all the bulb will do from the app (plus dimming, on/off). To switch to a different color, I’d have to go tack to my account on their website. Better, but still unacceptable.
I also found different levels of support for door locks. The Nexia (which partners closely and does a great job with Schlage locks, did only a minimal job with Kwikset locks. (I could manually lock or unlock, and see activity, but I couldn’t schedule the lock to auto lock a 10pm, only manually, and I wouldn’t be able to tie it to Geo-fencing either (such has haven’t the door unlock automatically when I pull the car into the driveway). With my SmartThings I can accomplish those things with both Kwikset and Schlage locks.
No solution is perfect, but with Z-Wave, it’s important to get a Hub that really is aggressive at supporting most of the major, and many minor products.
So far, of the four we’ve worked with, Wink and SmartThings are much better, although I understand HomeSeer has done a lot since I retired my outdated one. Choosing the right hub is very important.
Sure you can change out your Hub for a different brand, down the road, but your installer is going to be extremely busy, un-enrolling each device from it’s old Hub and configuring for the new one. (Think of it as a vaguely similar experience to moving from an Android to an Apple iPhone or the other way around – aka – a real pain.)
Also worth noting, some Hubs (i.e. the Nexia) have monthly services tied in for a fee (typically around $12 a month or less), others like Wink, and SmartThings (so far) – free.
Now, though, that many Z-Wave hubs have diversified into supporting other formats, I find that my SmartThings, can control almost all of the devices in my house other than Bluetooth. They, for example, support the Zigbee Philips Hue bridge, allowing my SmartThings hub to control Hue lighting. I also have Lightify lighting which comes with a Zigbee based bridge, and again, they are partnered so work. By comparison, I believe the Wink has an internal Zigbee bridge. (I haven’t yet read Dave’s Wink review – publishing tomorrow.)
In other words, through my SmartThings App, I can control most of everything, but often I’m limited in terms of what the App can do
But lets get back to “ecosystems”, and look a little closer at Zigbee.
Zigbee and Zigbee Bridges
I’m still working on my “big picture” understanding of the Zigbee world, but I figure that’s fair as this is a fast evolving industry.
As I mentioned near the top of the page, the few Zigbee devices we’ve worked with so far are mostly lights (there are plenty of others, though). It makes sense, therefore that those have bridges (which are basically hubs). My Lightify Garden Spot outdoor RGB lights talk to it’s (sold separately) Bridge, which in turn talks wirelessly (Wifi) with the app on my phone. But since SmartThings works with Lightify for compatibility, my SmartThings Hub talks to the Bridge allowing me to control those lights as well.
Having a Zigbee compatible controller – such as the Wink, can allow some individual bulbs, as well as more typical stand alone devices – wall switches/dimmer, outlets, door and sensors, etc., to be controlled, but you will still require bridges to work with most if not all products that have their own bridges, such as Philips Hue lights. So, it appears, for example, that you can NOT buy two Philips lights, and control them (dimming, color, etc.) directly with a Zigbee hub like Wink, instead you would still need the Philips Hue Bridge. Dave using his Wink, for example discovered that he could control a particular Zigbee color light, but only for white and dimming, not color settings. So, plan on owning those bridges.
Here’s a list of products supporting Zigbee.
Remember, as with Z-Wave, just because a product is supported, does not guarantee that you can control, use, all features and capabilities from any Zigbee controller.
Try this links for more on voice control and eco-systems for home automation:
In this series (so far):
Smart Home Eco-Systems A-Z (Feature – Overview)
Smart Home A to Z – Personal Assistants: A is for Apple, Alexa
Smart Home A to Z – Standards: Z is for Z-Wave, Zigbee