Cement alternatives are materials that can replace or reduce the use of traditional Portland cement in construction. These alternatives often have lower carbon footprints and can enhance the sustainability of building projects. Common examples include fly ash, slag cement, and natural pozzolans, which are byproducts of other industrial processes or naturally occurring materials. Using cement alternatives can improve the durability and performance of concrete while also reducing environmental impact. For instance, fly ash can enhance workability and reduce the heat of hydration, making it a popular choice in large-scale construction. Overall, these alternatives contribute to more eco-friendly building practices.