Occupancy schedules in building spaces play an important role in evaluating a building¿s energy performance. This work seeks to identify disparities between different occupancy estimation techniques; standardised occupancy profiles found in literature, business processes¿ based profiles through interviews and accurate profiles from real on-field measurements. The occupancy diversity profiles of secondary spaces in a healthcare facility building are analysed through descriptive statistics and t test methods over different time horizons. Occupancy measurements are obtained by utilising a novel, robust and highly accurate real-time occupancy extraction system which is established through a network of depth cameras. Results indicate that the utilisation of real occupancy data, along with elaboration of the business processes that take place in building spaces have the potential to support more precise profiles in Building Performance Simulation software tools.