This invention relates to a mixed composition for making structural building materials or articles; wherein the composition comprises a prepared or reprocessed solid or sludge waste material such as impure lime obtained, in particular, from water treatment plants, and further comprises a reinforcing material such as fiberglass, metal material, sisal fiber, or plastics, and also comprises a polymeric material which preferably includes polyurethane foam. A coloring agent is added the composition to give a distinctive color to the structural building materials or articles such as shingles, panels, sidings, walls, and logs, all replicating products made especially from wood.