The Role of Moisture in the Built Environment for Occupant Wellness: A Critical Review

Moisture is present in every feature of the anthroposphere, and its occurrence in air has a profound impact on life. It has an impact on all aspects of the built environment, inside which modern occupants spend nearly 90% of their time. While moisture’s influence on the individual aspects of functional building performance, indoor air quality (IAQ), thermal comfort, and occupant health is well recognized, holistic studies examining the interdependencies among these aspects remain lacking, with the existing literature fragmented across climate studies, building physics, thermal comfort, epidemiology, and medicine. This review adopts a critical synthesis approach to trace moisture’s role across these disciplines, from the outdoor microclimate through the building envelope to the indoor environment and occupant. The synthesis reveals moisture’s dual role as a determinant of IAQ, thermal comfort, and occupant wellness, and as a physical driver of building material durability, structural performance, and operational energy consumption, with these moisture-driven interactions across scales found to be tightly interdependent. Based on this synthesis, a multi-disciplinary framework is proposed, linking the microclimate, building, occupant, and planetary health levels through moisture, identifying key interdisciplinary research gaps and providing a foundation for practical interventions toward occupant and planetary health.