PURPOSE: To manufacture a flooring material, inexpensive, strong and of good dimension accuracy by kneading one or two or more of waste components such as slag and powder and grain of waste thermoplastics while pressurizing, solidifying a kneaded material through an extruder and/or rolls when the material is softened into the rich cake state and providing the material with the given strngth and dimension.

CONSTITUTION: One or two or more of waste components such as slag, cinders and sludge and powder and grain of waste thermo-plastics such as polyethylene, vinyl chloride resin are put into a kneader and kneaded therein while being pressurized. In the initial kneading in which no lubricant exists, friction heat is generated between two components to create strong temperature rise, and polyethylene resin and the like are melted and bonded with cinder powder, softened and formed into the rice cake state to form lump shapes. Then, a mixture of lumps is put into an extruder and further passed through rolls to form a plate-shaped material. The plate-shaped material is put into a forming machine of pressurizing type in which the size and thickness of a flooring material are fixed, cooled and solidified to manufacture the flooring material of given strength and dimension.