Impact of accelerated weather aging on building energy efficiency using cement and gypsum boards with...

This study evaluates the performance and durability of phase-change material (PCM)-enhanced gypsum and cement boards subjected to accelerated weather aging, and their subsequent impact on building energy efficiency. Gypsum and cement boards containing 10-30% shape-stabilized PCM (ss-PCM) were exposed to controlled environmental stress. Thermal conductivity, specific heat, emissivity, solar reflectance, and latent heat storage capacity were measured before and after aging. Prior to aging, gypsum boards achieved up to 5.4% net annual energy savings, and cement boards up to 4.8%. Post-aging, gypsum samples exhibited a near-complete loss of latent heat capacity, reducing energy savings to 0.7%. In contrast, cement boards with 30% ss-PCM retained approximately 54% of their original latent heat, retaining 3.1% net energy savings despite a 35% reduction relative to pre-aging performance. Solar reflectance increased in gypsum boards (up to 38.8%) after aging, while thermal conductivity remained stable or improved in cement boards. Emissivity values remained high (> 0.90) across all samples, with only minor deviations after aging. These findings highlight the relative environmental durability of PCM-enhanced cement boards and highlighting the influence of matrix composition and PCM encapsulation on sustaining energy performance under accelerated aging conditions.