Nathan Van Den Bossche

Professori, University of Ghent

Professor Nathan Van Den Bossche is Associate Professor Building Physics at the Faculty of Engineering and Architecture of Ghent University, Belgium. He holds master degrees in engineering, architecture, and real estate, is court expert in litigation cases for building pathologies. He is a certified carpenter and built his own house. He teaches courses on building physics, building science, and real estate. His scientific research focuses on building envelopes, including hygrothermal modelling, watertightness, airtightness, building pathology and damage analysis. Statistical analyses and case-studies for insurance companies steward his research, aiming to bridge the gap between theory and reality. One of the dominant research tracks is quantifying rainwater management in façade systems by means of full-scale test setups, and integrating this information in hygrothermal simulations. Next to that, his group develops practical tools for the building industry to conduct hygrothermal risk assessment.

Prof. Van Den Bossche is head of the Test Centre for Façade Components and author of more than two hundred peer-reviewed journal articles, conference papers, and book chapters. He is reviewer for 15 journals, and board member of the Journal of Building Physics. As a consultant he has been involved in projects by leading architectural offices such as Zaha Hadid Architects, Neutelings Riedijk, Renzo Piano, Ian Simpson, and Jean Nouvel. Furthermore, he worked half a year at the National Research Council in Canada and was appointed a guest professor at Politecnico di Milano for a year.

 

Keynote 28.10. klo 9.15

Why building physics did not solve moisture problems (yet)

In most countries, moisture-related pathologies cover more than 50% of all damage cases. Even though in recent decades there have been significant advancements in the field of building physics, that percentage has not declined. What are we doing wrong? There are 3 main reasons. First of all, the field of building physics develops models that allow to predict temperatures and moisture contents over time, but the validation of these models is often very problematic. Secondly, degradation models are adopted for which the validation is even more problematic. Thirdly, and most importantly, the field of building physics thrives on bias. Physics provides equations for heat flux, vapour diffusion, and capillary transport. In contrast, wind driven rain loads, rainwater runoff, rain infiltration, drainage capacity and local deficiencies are not easily quantified. Façade engineering in the context of climate change is thus confronted with opposing views: should we rely on what has worked in the past (but perhaps not in the future), or should we engineer innovative solutions (relying solely on the few phenomena we can calculate)? This keynote speech makes an argument for quantifying water management in façades and designing moisture tolerance. A methodology was developed to quantify watertightness, predict how much water will penetrate into each layer of a wall, and how to simulate this in HAM models. Finally, this also opens the door towards a new research paradigm. Next to the traditional bottom-up approach in building physics, we need a top-down approach where tools are trained by field performance.