HABot’s ontology is based on the Brick Schema. See HABot Walkthrough (2/n): Semantic Tagging & Item Resolving. I can’t say I’m an expert in either ontologies so can’t say what the overlap is or how they might be used together, if at all. But I did want to point out that there is already a somewhat formal ontology built onto openHAB for use in HABot in addition to the informal ontology we have with our Item types.
On a first look at it, I’m not sure that I like the way they separate the technologies like that. In an OH context, wouldn’t one want to have one “Switch” instead of a zwave:BinaryPowerSwitch and a knx:DPT_Switch?