## 1 Introduction
Furthermore, by augmenting the thermal mass of gypsum and cement boards, PCMs extend the period over which thermal energy is released or absorbed, beneficial in maintaining stable indoor temperatures in data centers, laboratories, and manufacturing facilities [16]. The addition of EMI shielding additives into building boards also plays a critical role in safeguarding against electromagnetic interference, crucial in environments housing sensitive equipment or systems reliant on uninterrupted electronic operation. This advancement ensures the reliability of electronic and wireless communication systems in commercial settings, including offices, hospitals, and research facilities [17]. Beyond thermal and electromagnetic considerations, this integration significantly contributes to meeting safety standards and regulatory requirements, addressing thermal insulation, fire resistance, and electromagnetic compatibility concerns. These advanced building boards offer a comprehensive solution that streamlines the construction process, reduces compliance-related risks, and enhances the overall safety and efficiency of commercial buildings. In summary, the combination of PCMs and EMI shielding additives into gypsum and cement building materials heralds a new era in construction technology. It not only improves thermal regulation and energy efficiency but also extends thermal mass capabilities, ensures reliable EMI protection, and streamlines compliance with safety and regulatory standards, thereby offering a multifaceted advantage across a wide array of commercial applications. Significant studies in the literature have delved into integrating carbon-based materials with shape-stabilized PCMs into composite cement or gypsum boards [1; 18]. [PERSON] et al. showed that concrete panels incorporated with paraffin-oil palm kernel shell-activated carbon exhibit increased thermal lag and reduced peak temperature during the phase transition of composite PCM [19]. [PERSON] and [PERSON] reported the preparation of cement composites with n-octadecane stabilized on a diatomic/carbon matrix [20]. The developed heat-storage cement mortar has been found to mitigate fluctuations in interior temperature, showcasing significant potential for energy savings and enhanced thermal comfort in the built environment. [PERSON] et al. reported that the incorporation of SAT-urea eutectic salts encapsulated with modified commercial-activated carbon in gypsum could slowly reduce the thermal conductivity and significantly improved the thermal inertia of the composites [21]. Finally, in our recently published work [22], the incorporation of activated carbon/RT18 HC into gypsum boards resulted in composite gypsum boards with improved thermal storage and EMI shielding properties, compared to standard gypsum boards. In this study, we present a novel investigation into the advancement of building materials with dual functionalities by incorporating gypsum and cement boards with shape-stabilized organic phase change materials (ssPCMs). This ssPCM consists of n-octadecane (OD) stabilized on carbon red-mud foam (CCF). Our previous research has extensively examined the thermal and electromagnetic interference (EMI) shielding properties of OD@CCF composites, demonstrating their effectiveness in thermal management and EMI reduction in electronic devices [8]. Our current research focuses on assessing the impact of different percentages of this additive on the thermal storage capacity and EMI protection capabilities of gypsum and cement panels. We conducted experiments under real conditions to simulate real weather scenarios using a custom-designed environment chamber, following the experimental approach of [PERSON] et al. [23]. Our current study focuses on assessing the impact of varying percentages of this additive on the thermal storage capacity and EMI shielding abilities of gypsum and cement boards. We conducted experiments under real-world conditions, simulating realistic weather scenarios using a custom-designed environmental chamber.