Bio-Based Building Envelopes with Phase Change Materials: A Thermal Lever for Carbon Neutrality in Mediterranean Buildings

The decarbonation of the building sector is a major challenge in the context of the 2050 carbon neutrality target, particularly in Mediterranean regions where cooling energy demand is steadily increasing. In this context, the optimization of building envelopes through passive thermal strategies represents a key lever for reducing operational energy consumption and associated greenhouse gas emissions. This study investigates the thermal, hygrothermal, and environmental performance of bio-based building envelope solutions incorporating phase change materials (PCMs). Several wall configurations are analyzed, including conventional reference walls and alternative assemblies based on plant-based insulation materials, such as hemp wool and wood fiber, with and without PCM integration. Dynamic hygrothermal simulations are carried out using WUFI Pro to assess heat and moisture transfer under representative Mediterranean climatic conditions. The results highlight the significant contribution of bio-based materials combined with PCMs to the improvement of indoor thermal comfort, the reduction of heating and cooling loads, and the mitigation of peak temperatures. Furthermore, the integration of PCMs enhances the thermal inertia of lightweight bio-based walls, leading to a better alignment between energy demand and climatic conditions. From an environmental perspective, these solutions show a strong potential for reducing the carbon footprint of building envelopes, supported by biogenic carbon storage and lower embodied energy. Overall, this work demonstrates that bio-based envelopes integrating phase change materials constitute an effective thermal lever to support the transition toward low-carbon and climate-resilient buildings in Mediterranean regions.

Work In Progress