Future of the Industry Foundation Classes: towards IFC 5

The buildingSMART Technical Roadmap, published in April 2020, was the start of multiple modernization efforts for buildingSMART Solutions and Standards. The modernization, modularization, and normalization of the Industry Foundation Classes (IFC) is one of the priorities. A taskforce has been working on restructuring the core of IFC for the IFC 5 developments. The following topics are discussed and researched (a) modularization of IFC (b) normalization of the IFC object trees and relations (c) language independency of the base data structure (d) modernization of the deployment tools and procedures for maintaining IFC. This paper reports progress on all these topics.The normalization of the object tree is an integrated effort that involves changes in the use of objectified relations, property sets and predefined types. The modularization provides interoperability between domains and a solution to easily support incremental updates in software implementations. This so called 'late binding' approach and the consequences on the IFC schema have been researched and reported in this paper.The paper is a progress report with an overview of considerations and work done so far. It will end with a discussion chapter about consequences of the modernization work and a call for participation in further developments.Urban Data Scienc