Fly ash bricks are a type of building material made from fly ash a by-product of burning coal in power plants. Fly ash is a fine glassy powder that can be used as a partial replacement for cement in concrete. Fly ash bricks are typically lighter in weight and less expensive than traditional clay bricks. They are also more energy-efficient to produce. Fly ash bricks are made by mixing fly ash with water cement and other additives. The mixture is then compressed into molds and cured. The curing process can involve steaming the bricks or allowing them to air dry. Fly ash bricks can be used in a variety of applications including walls foundations and pavements. Fly ash is a waste product that can be reused in fly ash bricks reducing the need to landfill it. Fly ash bricks are typically less expensive to produce than clay bricks. Fly ash bricks are lighter than clay bricks which can reduce the weight of a structure and make it more earthquake-resistant. Fly ash bricks can provide better insulation than clay bricks which can help to reduce energy costs. Fly ash bricks can absorb more water than clay bricks which can be a problem in areas with high humidity.