<p>Expanded graphite (EG), a highly porous and low-density carbon material, has been incorporated as an additive in cement concrete, foam concrete, geopolymers, bricks, and gypsum due to its exceptional thermal, mechanical, and chemical characteristics. The performance-enhancing roles of EG in these materials are highlighted in this paper. EG improves the thermal insulation, fire resistance, and electromagnetic shielding properties of cement concrete without significantly affecting its mechanical strength. In foam concrete, EG contributes to reduced density, tunable thermal conductivity, and improved acoustic behavior, which are beneficial for lightweight and energy-efficient structural applications. In geopolymeric materials, it can serve as a filler to enhance mechanical strength and thermal performance while enabling a more sustainable utilization of industrial by-products. As EG improves thermal insulation and reduces density, its inclusion in brick production results in more energy-efficient building components. Additional advantages of EG include enhanced fire resistance, thermal regulation, and moisture control in gypsum-based composites. The application of EG in these materials demonstrates its potential to address current challenges in construction such as energy efficiency, sustainability, and durability. Although EG shows considerable promise as a construction additive, further studies are needed to assess its cost, scalability, and long-term performance under diverse environmental conditions. In conclusion, this review confirms that EG can play a pivotal role in developing next-generation, high-performance, and environmentally sustainable building materials.</p>