GLOBAL WARMING POTENTIAL OF BUILDING CONSTRUCTIONS BASED ON HEAT AND MOISTURE TRANSPORT ANALYSIS

Global warming potential is one of the most important life cycle assessment indicator, which shows how much heat a greenhouse gas traps in the atmosphere relative to CO2. In this study, we calculated the global warming potential of a highly insulated building construction detail of a residential nearly-zero energy building based on numerical simulations. To calculate the heat loss of building constructions, which is necessary for estimating the operational energy demand in the use phase of the building, we compared two numerical simulation methods: 2-D thermal simulations and 2-D conjugated heat and moisture transfer simulations. Besides that, we compared the effect of selecting different thermal insulation materials for insulating the building constructions, such as EPS, mineral wool, and wood wool. We then compared the thermal and linear thermal transmittances from the simulations besides evaluating the moisture transmittance behaviour of the constructions. In all examined scenarios, the constructions with mineral wool ended up being the highest impact alternative, while EPS was the lowest for walls and wood wool was for wall corner joints. We also found that including the wall corner joints in global warming potential calculations could increase the overall global warming potential of an average-sized family house by 10%. Our study shows the heat and moisture transfer induced differences between thermal insulations, and demonstrates that heat and moisture transfer modelling-based life cycle assessment indicator of building construction details gives valuable additional information designers to choose the proper thermal insulation.