Building construction has gone through significant change with the emerging spread of ICT during last decades. “Intelligent buildings” are equipped with building automation systems (BAS) that can be remotely controlled and programmed and that are able to communicate and collaborate. However, BAS aim to facilitate operation of the building and do not provide sufficient support for strategic level decision support. This article presents adaptation of Semantic Sensor Network ontology for use in the field of building operation analysis. The Semantic BMS ontology enriches the SSN with model of building automation datapoints that gather operation data and describe the interconnections between BAS devices, algorithms and influenced or monitored properties of a building. Proposed ontology allows facility managers to query BAS systems in a way that is convenient for tactical and strategic level planning and that is unavailable in current state of the art systems.