Determination of optimal thermal inertia of building materials for housing in different Chilean climate zones

In recent years, several studies on residential energy consumption and new strategies for its reduction have been carried out. The literature reports that thermal inertia can have an influence on energy demand and, to a greater extent, on the thermal comfort of the buildings. The performance of thermal inertia in buildings located in different regions or countries has been analysed, comparing structures or materials having high and low thermal inertia through energy simulations or empirical studies. However, the optimal thermal inertia of a building according to different climates has not been established. In this study, optimum values were determined for the different properties that define thermal inertia (thermal conductivity, specific heat capacity, and density) that would allow to maintain the indoor annual operative temperature within the thermal comfort range (18–24°C) of a standard dwelling. Energy simulations were carried out in DesignBuilder using climate data from 10 cities in different Chilean climate zones. The results show the minimum thermal conductivity as optimal regardless of climate (0.025 and 0.03 W/(m∙K)), while the optimal density ranges fluctuate between 1800 and 2500 kg/m3 varying according to the climate zone. Finally, it was determined that specific heat capacity was not influential in the thermal comfort of the analysed dwelling.