Professor Bjarne W. Olesen is a leading international expert in indoor environmental quality and building energy performance. He is a professor at the Technical University of Denmark (DTU) and a former President of ASHRAE (2017–2018). Over several decades, he has played a key role in the development of international standards for thermal comfort, ventilation, and energy performance through his work in ISO, CEN, and ASHRAE committees. His research and professional contributions have significantly advanced the understanding of indoor climate, linking energy efficiency with health, comfort, and human performance in buildings.

In this Expert Talk, Professor Olesen reflects on the evolution of thermal comfort, questioning the adequacy of traditional steady-state models in capturing real occupant experiences in today’s dynamic environments. He also addresses the persistent gap between established standards and the actual performance of buildings in practice, highlighting where current approaches may fall short. The discussion further explores the growing importance of integrating indoor environmental quality within the Energy Performance of Buildings Directive (EPBD) framework and what is needed to translate policy into tangible improvements. Finally, he shares his perspective on the priorities that should shape future standards, particularly in balancing energy efficiency, occupant wellbeing, and performance in the face of climate change.

The BUILD UP Expert Talks series is an initiative of the BUILD UP portal and features face-to-face interviews with experts from across Europe, offering diverse perspectives on key topics related to energy efficiency and renewable energy in buildings. These interviews align with the Topic of the Month and explore it in depth, providing valuable insights, experiences, and expertise to the BUILD UP audience.