Plug-in Temperature and Humidity Sensors (Z-Wave maybe?)

[chairstacker]

If it can be something else than Z-Wave I’d recommend the Xiaomi Aqara Zigbee sonsors connected with the a Zigbee2MQTT-dongle:

Zigbee2mqtt: getting rid of your proprietary Zigbee bridges (Xiaomi, Hue, TRADFRI)

Hi all, Because of the irritation I got from my Xiaomi Zigbee bridge (talking in Chinese, sending data to Chinese cloud and a bad app) I started to look if it is possible replace the Xiaomi gateway with a more open solution. I found that Andrew Linden had a proof of concept for this. It bridges events and allows you to control your Zigbee devices via MQTT. In this way you can integrate your Zigbee devices with whatever smart home infrastructure you are using. I found this idea very interestin…

Yes, you need to buy the kit to flash the USB thingie, but the sensors themselves are only $11 a pop if you buy them on AliExpress.