The specifying community and local municipalities have experienced a strong surge related to design and use of recycled construction materials. Fly ash is characterized by LEED as an industrial by-product which enables the user to qualify for recycled material points.
In addition to fly ash, other coal combustion products (CCP) such as bottom ash and flue-gas desulfurization (FGD ash) may be used to produce "green" construction materials. For example, wallboard has a high gypsum content for which FGD ash may be substituted. Concrete masonry units, paints, carpet backing, and asphalt roofing shingles may all be produced using CCPs as recycled materials.