This is a Facility Management Building Energy Ontology for Renovative Design Decisions. The ontology provides different classification aspects, according to what written FM best practice policies can be systematically classified and stored in a form of natural text, as well as in the form of machine-readable rules. Respectively, the ontology contains the Paragraph 405.9.1.1, Paragraph 405.9.1.2, and Paragraph 405.9.1.3 of the International Energy Conservation Code (IECC) 2021 in the form of natural text, as well as in the form of SWRL rules. Data format: OWL file format Software: Protege version 5.5.0 This ontology is part of a Doctoral Dissertation, titled as: Towards a BIM-supported Facility Management Knowledge Management System for Energy Efficient Building Operations by Rule-based Code Compliance Checking DOI: http://dx.doi.org/10.14279/depositonce-16040 Contact: Zsuzsa Besenyƶi besenyo@htw-berlin.de