The best Wi-Fi door/window sensors for Home Assistant
Disclosure: This post contains affiliate links. If you click through and make a purchase, I will earn a commission, at no additional cost to you. Read my full disclosure here.
Despite the deep integration of Zigbee and Z-Wave with Home Assistant, Wi-Fi devices are still prevalent. Some devices make use of Wi-Fi out of necessity, for example security cameras need the bandwidth, while others use Wi-Fi to fill a gap in market. The devices featured in this list of the best Wi-Fi door/window sensors for Home Assistant don't need to use Wi-Fi for any particular reason. Sending an on or off signal on each change in state doesn't require much bandwidth. However, there might be some out there that don't want to make use of an added adapter for Zigbee or Z-Wave, and instead want to utilize the existing Wi-Fi network.
As you can tell by the table of contents, this list is rather short. Especially when we compare it to what is available for users of Zigbee. I, personally, would not use any of these Wi-Fi door/window sensors. Not because I think they are bad, but because the use of my existing Zigbee network is better suited.
When deciding to stick to Wi-Fi, you need to keep in mind that an access point can only handle a certain number of connections. The more devices you add, the more slowdowns and disconnections you will be experiencing.
There is only one benefit that Wi-Fi door/window sensors have over Zigbee and Z-Wave equivalents: there is no hub required. Because they use Wi-Fi for communication, they can directly connect to your access point, without a hub. However, there is more than one downside of using Wi-Fi door/window sensors:
Wi-Fi is power hungry, meaning that most sensors will need their batteries replaced more frequently than those using Zigbee or Z-Wave.
Too many Wi-Fi devices connected to your access point can slow down speeds for other devices such as phones and laptops.
Making sure the device can't call home requires knowledge of networking.
You will need to research which devices can be controlled locally and which can only communicate using the cloud.
Shelly Door/Window 2: Stamina, features, and no competition
When it comes to Wi-Fi switches, relays, dimmers, plugs, and also sensors, Shelly is the first vendor to consider. I would even go as far as to say that Shelly Door/Window 2 is the only Wi-Fi door/window sensor option for users of Home Assistant. Even for those not using Home Assistant, it is the best Wi-Fi door/window sensor, with none other coming close.
Shelly Door/Window 2 is more than just a contact sensors. Integrated in to the device is a temperature and light sensor. While it does have more sensors than any of the previously discussed Zigbee alternatives, it also costs more than double as much (~US$28). It is powered by two CR123A batteries with an estimated battery life of two years. If you do decide to purchase this sensor, you should be aware that it does not ship with any batteries, increasing its actual price.
The Shelly Door/Window 2 sensor uses your home WiFi network, no additional controllers are required.
Be aware of temperature fluctuations and keep your home comfortable at any time with its temperature sensor.
The device has an integrated LUX sensor.
By using the ShellyForHASS custom component, it is possible to integrate the Shelly Door/Window 2 with Home Assistant without the need of having it permanently connected to the cloud. This custom component will automatically discover any Shelly devices and uses CoAP and REST for communication. Thus, there is no need to set up an MQTT broker for the integration. There is no extra configuration of the Shelly Door/Window 2 required, and state changes are almost instant thanks to local push.
The only alternative to the Shelly Door/Window 2 you might want to consider is the SONOFF DW2-WI-FI Wireless Door Window Sensor. Two AAA power this Wi-Fi door/window sensor, which can keep it alive for a reported three months. One benefit it does have is that the magnet and the sensor can be placed up to 5 mm apart, whereas most other sensors max out at 2 mm.
The easiest way of integrating SONOFF devices with Home Assistant is by using the SonoffLAN custom component. Even when using SonoffLAN, the SONOFF DW2-WI-FI can only be access by Home Assistant through the cloud. Consequently, it will have to be connected to the internet at all times and response times will be slower.
Add to those two major downsides the fact that you can't buy the SONOFF DW2-WI-FI on Amazon, and only on AliExpress. That leaves the Shelly Door/Window 2 as the only viable option and the best Wi-Fi door/window sensor for Home Assistant.
