IFC Classification for FOSS HBIM: Open Issues and a Schema Proposal for Cultural Heritage Assets

The IFC (Industry Foundation Classes) open format has been developed by BuildingSMART and regularized through ISO standards. It has been implemented into a BIM (Building Information Modeling) informative system for the AEC industry (Architecture Engineering and Construction). The IFC format has changed interoperability processes concerning architectural and technical entities in a semantic way. However, because this standard open format was specifically designed for the modern AEC industry, it may not cater to the demands of cultural heritage assets. Since IFC classification is fundamental for informative systems, it should become a standard also concerning heritage assets, even if nowadays there is no regularized IFC classification for historical existing buildings. Specific cultural heritage peculiarities therefore need semantic classification based on historical asset families. For this reason, this work is based on a proposal and experimental IFC classification implemented inside an HBIM open source software (FreeCAD), whereby limitations of IFC standards can be overcome thanks to the freedom of access to libraries and codes. Moreover, this work is based on IFC objects management outside the platform for interoperability purposes.