Thermal resilience to climate change of energy retrofit technologies for building envelope

Over the past 20 years, energy retrofit measures for buildings, such as thermal insulation and window replacement, were standard practices. To further enhance the energy performance of building envelopes, innovative technologies like double-skin façades, opaque ventilated façades, and green roofs are also available, fostering a positive interaction between buildings and the environment. The paper evaluates the resilience of building technologies in relation to climate evolution and warming, considering both general (chronic) overheating and (spot) extreme events. Energy performances of a reference office, applying traditional and innovative energy retrofit packages, are analyzed under historical, current, and future weather conditions across three locations. The research questions and novelty are whether both traditional and innovative energy retrofits remain effective under climatic evolution and how the effectiveness of traditional versus innovative building technologies changes. Regarding space-heating energy demand, both retrofits are equally effective and resilient. For space cooling, the innovative package proves more effective under moderate conditions. However, under extreme outdoor conditions, traditional thermal insulation technologies may be more effective than innovative technologies. Attention is required when indoor temperatures are free-floating, as excessive thermal protection can imply indoor overheating. Ultimately, the thinking approach for energy retrofit measures should focus on long-term effectiveness and resilience.