If you’re even moderately interested in smart home automation, you almost certainly know of the term “Z-Wave”. You’ve seen it on the product pages of your favorite gadget webshop, on smart home blogs and on the websites of big tech publications. And you probably wondered: “What is Z-Wave, and why is it important?”
Z-Wave is a Smart Home Technology. More specifically, Z-Wave is a wireless protocol. It’s a wireless technology designed specifically for control and monitoring in residential environments. In other words, a technology that’s used in many products that can control and monitor your homes.
Z-Wave is the biggest technology in wireless control of smart home devices. It has become the biggest by offering a couple of interesting advantages.
For starters, it has a standardized protocol, meaning all devices use (almost) the same wireless commands. Next to that, all Z-Wave communication is two-way: devices confirm commands given to them to ensure operation. Also, due to the wireless band used, it provides relatively good range in homes - even through walls.
It only requires low power, allowing for battery-powered devices. Lastly, it is built as a mesh network. This is a technology that makes the wireless network stronger when more devices are added.
According to the Z-Wave Alliance (yes, the technology has its own Alliance) there are over 2100 Z-Wave devices available and there are over 70 million Z-Wave products installed worldwide.
Z-Wave is extensively used in residential systems, and consumer-oriented smart products. It’s used by big names like Honeywell, Yale, Fibaro and Homey. To reassure quality control, the Z-Wave Alliance have certified thousands of Z-Wave devices. It’s a technology that is incorporated into nearly everything. From small Z-Wave modules such as sensors, to Z-Wave controllers, to smart locks.
To get started with Z-Wave automation, you need at least two devices - although you probably end up wanting more: an end device (light bulb, switch, sensor) and a Z-Wave controller. The Z-Wave controller, also called Z-Wave Hub or Z-Wave Gateway, is the heart of your Z-Wave network. It provides the interface between you and the devices, often in the form of an App. It coordinates the network and registers the new devices.
To get started, first set up your Controller and register it on your WiFi network. This way, your mobile phone can access it and you can get started adding the Z-Wave end devices to your controller. We recommend pairing the end devices close to you controller, as some devices pair in a low-power mode, limiting their wireless range for security reasons. After pairing, you can place it in its final location in your home.
Now, Z-Wave is a great technology, but not the whole world runs on Z-Wave. There are several other wireless technologies out there powering Smart Home. That is why we recommend using a universal controller like Homey. Homey is not only a Z-Wave controller, but can also control devices on your WiFi, via Bluetooth, using Infrared, and devices controlled via Zigbee, 433MHz and 868MHz signals. Now, this may or may not mean too much to you, but basically it means you can include many more cool brands and devices in your smart home system.
‘Not the whole world runs on Z-Wave’ means there are also alternatives to the technology being used in the home. As always with alternatives, each has their pros and cons. In the case of Z-Wave, the most notable alternative is Zigbee.
Zigbee is a technology that is in some cases comparable to Z-Wave. For example, Zigbee also features mesh networking to improve the network and range of the technology. Next to that, also all communications are two-way, it’s equally low power-hungry as Z-Wave and it features some standardization.
The latter also provides the difference however. Zigbee, as opposed to Z-Wave, is loosely standardized: manufacturers can use the standard commands, but can also opt not to use them, or to modify it to suit their specific wishes. In other words, Zigbee devices can choose not to completely follow the standard. In Z-Wave, this is not possible. This means in Zigbee, manufacturers have more freedom. However, it also means it’s often harder to have Zigbee devices from different brands to talk with each other.
The other difference is the band used. Z-Wave uses the 868MHz band (Europe) or the 900MHz band (US/ASIA), while Zigbee is on the 2.4GHz band. This makes Zigbee easier to deploy across countries, as all legislation allow free sending on the 2.4GHz band. At the same time, however, Zigbee can experience interference from WiFi networks, who also run on the 2.4GHz band. Also, lower frequency bands penetrate walls better. This means Z-Wave has a better range compared to Zigbee.
Zigbee chips are cheaper than Z-wave modules. This makes Zigbee popular at large vendors. For instance, the IKEA TRADFRI series of lightbulbs uses Zigbee, as does Philips Hue. Z-Wave, on the other hand, is implemented in a wider variety of different devices and brands, due to the further standardization and range.
At the moment, both technologies have their clear advantages and disadvantages. More importantly, both have interesting brands and products that uses them. That is why it’s hard to denounce a winner or even recommend one above the other. Z-Wave clearly offers a way better experience, reliability and range when it comes to sensors. On the other hand, in lighting Zigbee clearly has the most attractive products at the best prices. And in most use cases, you will want to combine the both. Choosing is hard, almost impossible. Luckily, Homey features both!
As stated above, Z-Wave (and also Zigbee) is a Mesh Networking Technology. This is a big advantage for a smart home system. Normally with wireless signals, there is one sender and one receiver. When the two are out of range, they can not reach each other. Also, more devices using the same technology can interfere with each other.
Enter mesh networking. Instead of all the senders and receivers shouting things to each other, devices in a mesh network actually work together. This means that messages are sent at times when the network is quiet, preventing interference. Also, it means that devices can act as a repeater for signals. This means a message can ‘hop’ via intermediary devices, greatly extending the practical range. Now, sender and receiver do not have to be in range to talk to each other - as long as there are devices placed in between them, they can be used as ‘stepping stones’ for the signal.
In Z-Wave, every device that is mains-powered (in other words, does not have a battery) acts as a repeater in the network. Every additional device therefore makes the network stronger. As a Z-Wave message can do up to 4 ‘hops’ in the network, the practical range of a Z-Wave network easily covers even the most expanded homes.
As it is with technology, things might become overwhelming. It seems hard to believe: all these different products from different brand working together in perfect harmony? There has to be a catch. That wall plug can’t possibly communicate with your smart lock? Don’t worry. Because of the way the Z-Wave Alliance, it’s the number one priority.
Another big plus for Z-Wave modules is that it uses a much lower transmission power than Wi-Fi, so it only requires batteries to make them work. And these batteries last for years! This makes Z-Wave a perfect solution for existing homes, where there is already some automation in place. You can easily add new tech around the house as you like, and keep upgrading and expanding the way you seem fit for you smart home automation.