Do Sonoff Zigbee Minis Work If the Hub is off?

Hi all, I’m having some work done to my house at the moment, and I’d like to build in smart home support. However, I don’t feel that my WiFi is reliable enough to go completely Smart, so I want hardware switches to still work in the event of my hub not being available.

I’m considering asking the electrician to install these: https://www.amazon.co.uk/dp/B08S3FCGQ6 SONOFF mini smart switches to be installed behind real light switches. However, I’m not sure what happens with these if the hub goes offline? Are the existing switches useless without the hub?

Those use a wireless mesh technology called Zigbee. Your ST hub does not need an internet connection for these to work. Your ST hub will need to be powered on though for them to communicate. In addition, the sonoff minis can we wired to the switch and act like a hard wired switch in that case, so an individual light can still work fine even without the ST hub. You just wouldn’t be able to remotely control them with the app.

The only thing I’d say on these is that the switch can become out of sync if you use the app for control. For example, you can flip it on with the app, but the physical switch will still look like it is off. If that is fine, your plan will probably work fine.