Development of sustainable heat resistive and storage panels for building envelope: An experimental and numerical study

Lightweight concretes (LWC) exhibit low thermal mass which results in increased summertime overheating and cooling demand. Form-stable phase change materials (FSPCM) with aerogel as a filler material were integrated into LWC in previous studies to overcome those issues. However, silica aerogel has poor compressive strength and high embodied energy. Therefore, this study used recycled expanded glass (REG) as a filler material with a stiffer surface and low embodied energy to develop heat resistive and storage panels (HRSP). The panels were prepared using a particle-density approach and their properties were tested following ASTM standards. Among the prepared panels, HRSP4 showed acceptable thermal (0.64 W/m-K) and structure (17.77 MPa) properties for medium load application. Dynamic thermal and energy simulations revealed that HRSP4 application in building envelope reduced summertime overheating by 12.4% at the cost of a 1% rise in wintertime undercooling due to high thermal storage of 628 kJ/m3. Moreover, in an air-conditioned building, HRSP4 reduced both cooling and heating load by 14% and 3% per annum, respectively, in the temperate oceanic climate of Melbourne, Australia. The lifecycle energy and CO2 emission with the HRSP4 envelope were reduced by 4.5% and 12% respectively, compared to the reference panel.