Abstract
To answer the urgent need to reduce thermal energy consumption of buildings, opaque façade technologies have evolved, increasing their thermal insulation and airtightness levels to effectively block energy flows. However, as evidenced by several research studies, envelope elements with high insulation levels are not always beneficial to optimise the energy performance of buildings. Indeed, releasing indoor thermal heat gains during certain cooling demand periods and harvesting solar heat gains during heating demand periods can reduce the operational energy needs of buildings. This is the most promising characteristic of Adaptive Opaque Facades; their ability to allow or block thermal energy exchange depending on the climatic conditions. According to some simulation-based analyses carried out in specific climates, building characteristics, and urban contexts, the annual energy demand could be reduced by up to 69% if the thermal properties of opaque building envelopes can be adjusted and controlled.