Hartwig M. Künzel is a globally respected leader in hygrothermics and Head of the Hygrothermics Department at Fraunhofer IBP. In this role, he oversees industry- and government-sponsored research focused on heat and moisture transport in building materials and systems. His responsibilities include scientific leadership, model development, team management, and strategic oversight of the department’s annual research programme.

During his PhD research, Hartwig developed WUFI®, the internationally recognised hygrothermal simulation tool that has become foundational to modern moisture control analysis in buildings. His work has significantly advanced the understanding of the interaction between heat and moisture within building envelopes and its influence on energy performance, durability, and occupant comfort.

Hartwig has contributed to numerous international research initiatives supported by the International Energy Agency (IEA), the European Commission, and multiple German ministries. He plays a central role in the development of international standards and guidelines, chairing the German national standards committee on moisture control and the CEN working group on the hygrothermal performance of building components.

An active member of ASHRAE since 1999, Hartwig regularly participates in technical and standards committees related to moisture management, insulation, and climate data. He served as the principal reviser for Chapter 25 of the ASHRAE Handbook of Fundamentals in the 2009 and 2013 editions and has authored more than 350 scientific publications, including journal articles, conference papers, and textbook contributions.

Hartwig holds a Diploma in Chemical Engineering from Erlangen University and a PhD in Civil Engineering from Stuttgart University. In recognition of his contributions to building science, he was appointed Honorary Professor at Stuttgart University in 2016.