What a building digital twin actually is versus a static BIM model, the three levels of twin fidelity, the data sources that feed one, real use cases in space utilization and fault visualization, and where the industry's hype currently outruns deployed capability.
A BIM model is a geometric snapshot of a building as of substantial completion; a digital twin adds a live, continuously updating connection back to the real building, so the model reflects the building's actual current state rather than what was designed or as-built years earlier. This module works through the fidelity spectrum from a purely geometric twin, through a semantic BAS-connected twin, up to a genuinely predictive, simulation-capable twin — and is direct about how much engineering effort separates the second level from the third.
By the end of this module you should be able to place a real deployed twin on that fidelity spectrum, explain what data sources and point-mapping effort actually keep a twin synced with a changing building, and evaluate a vendor's digital-twin claims against what the model can actually do rather than how it looks in a demo.