Värmetröghet i byggnader : En studie som undersöker en skolbyggnad utifrån olika materials värmetröghet samt dess klimatpåverkan genom en livscykelanalys

Sammanfattning: Thermal inertia is defined as “a measure of the responsiveness of a material to variations in temperature”. This means that materials with high thermal inertia will show small changes in temperature during a cycle of time and vice versa. This study aimed to evaluate the energy saving potential of thermal inertia which can be raised by the choice of various building materials. For this aim, a case study of a preschool building was used in which different configurations (i.e. different combinations of materials) of exterior walls and interior floors were studied using a building energy simulation program, IDA Indoor Climate and Energy (IDA ICE). The study mainly focused on the materials and configurations that yielded high thermal inertia where the results were compared with the as- built design of the preschool building in terms of heating and cooling demand as well as overheating. Furthermore, a life cycle analysis (LCA) was conducted using a LCA program, i.e. One Click LCA. This was done in order to understand better how the choice of building materials, besides the thermal inertia and its energy-saving potential, could affect the carbon footprint of a building from a life cycle perspective. The results indicated that there aren't significant differences in heating demand between the studied material configurations and the reference building. However, moderate changes were observed in both cooling demand and overheating, especially for some materials that have higher thermal inertia. A common denominator among these configurations was that all consisted of interior floors of either wood or massive wood. However, in terms of ”CO2 emissions”, significant differences between the studied materials and reference building were observed. In general, it was found that the life carbon impact increased in the most material configurations. This increase was more than offsetting reductions obtained in the operational ”CO2 emissions”, i.e., the reduction in energy demand caused using materials with higher thermal inertia. The configurations that performed better than the reference building from a life cycle perspective were the ones that didn’t consist of concrete, neither for exterior walls or interior floors.