Hygrothermal Analysis of Retrofitted Buildings in the Campus of Lund University

Abstract: As climate change have become generally accepted as a potential problem, reducing the greenhouse gas emissions and global energy demand has become an important research topic. This have led to an increased interest towards the retrofitting of the existing building stock, including cultural protected buildings. Due to the cultural protection, carrying out major alteration such as exterior wall retrofits are often not possible, leaving interior retrofitting as the only option. Previous studies have however shown that interior retrofitting poses great risks with respect the hygrothermal performance. This study focused on assessing the long term performance of various energy retrofitting measures for the exterior wall and roof constructions with respect to energy- and moisture performance, window replacement was not included. Carried out for two protected buildings in the campus of Lund University, and the adaptability of the retrofitted measures towards the future climate conditions, simulated until year 2100. The economic- and environmental feasibility of the retrofitting measures was furthermore determined through LCC and LCA. Results showed the smart vapour retarder assemblies would outperform both the capillary active as well as the traditional assemblies using PE-foil, with respect to the hygrothermal performance. However, the water repellent coating showed to be vital for any of the wall assemblies to problem free. A potential reduction of the heating demand by 20-30% was shown for the retrofitted walls, while only 5% for the retrofitted roof constructions. The retrofitting measures were shown to be economic infeasible, while the wall measures were shown to be environmental feasible.