Connecting "dumb" devices to openhab with wires

What methods are available to connect a variety of non-networked devices to openhab? For example, lights, a heater, a water heater, pumps, etc which aren’t “smart”. Would I need to connect them to the network in order to make it work with openhab? Could I wire them straight into the raspberry pi and make that accessible to openhab?

For 240v/120v powered items. You could plug them into smart plugs. Or you could wire inline some Sonof basic modules.
All of which is best to be flashed to Tasmota, or if theyre zigbee devices use zigbee2mqtt on the RPI and get a zigbee dongle.

For Items with IR remotes, you could get a zigbee IR remote, or make your own with a wemos d1 mini and IR LEDS.

I agree with Christopher

or…

or… Shelly 1s or whatever

or…

check out new GPIO binding here

Can you please elaborate further on this ? I have a Tuya Wifi IR universal remote. Is it possible to bind this into openab ?

Anything Tuya related can usually be flashed with Sonoff.

Shelly and Sonoff devices are cheap and use regular WiFi (Sonoff also have zigbee). I’ve also just published a native binding for sonoff, or as @Christopher_Hemmings said you can flash if you want with tasmota firmware.

Z-wave, for me, has been the most reliable protocol in my home. My lights all run on Fibaro dimmer modules. You will however need to purchase a usb stick such as the aeotec gen5+ and they are not the cheapest as it’s a licensed product. They operate at a much lower frequency than WiFi so you do not get the interference that is associated with 2.4ghz.