There are 3 repositories under ifc4 topic.
A .NET library to work with data in the IFC format. This is the core component of the Xbim Toolkit
A browser-based BIM viewer, built on the xeokit SDK
A client-side IFC parser
AI281X Degree Project in Architectural Design and Construction Project Management
Extract different data from IFC file(4 - 2x3), Dealing with elements like Columns and beams.
Manager for structured building properties - based on IFC, but highly simplified. Should convert nicely both ways and to other data formats.