Development of Thermally Insulating Gypsum Boards Blended with Quartzite and Fiberglass Waste

The construction industry generates approximately 45% of the world’s total waste, highlighting the need for sustainable solutions. This study investigates the incorporation of quartzite waste (QW) and fiberglass waste (FW) into the production of gypsum plasterboard to reduce its environmental impact while maintaining its structural performance. The optimum formulation (MQ-20) was determined by replacing 20% of the gypsum with QW, based on the observed free water loss and crystallization water. The physical, mechanical, and thermal properties of the reference and modified boards were evaluated. The results showed that the MQ-20 samples exhibited a 30% reduction in flexural strength compared to the reference, while still exceeding regulatory standards. In addition, the MQ-20 samples had a lower thermal conductivity (0.54 W/(m∙K)) than the reference (0.58 W/(m∙K)). Fire-resistance tests showed that the inclusion of QW and FW reduced the size and number of cracks, improving the structural stability of the plasterboard at high temperatures. This research demonstrates that the incorporation of industrial waste into plasterboard is a viable and environmentally friendly approach, providing both mechanical and thermal performance benefits. These findings provide a basis for future studies aimed at developing sustainable building materials with improved functional properties.