To lay a terrazzo floor, put grooves into the concrete slab with a circular saw. Spray the floor with a pressure washer, and put metal dividers into the grooves. Mix the marble chips and cement, and spread the mixture on the floor with a roller.Continue Reading
Put a masonry blade on your circular saw, and put grooves that are an inch deep by 3/8 inch thick, spaced at least a yard apart diagonally. Sweep the floor, and spray thoroughly with water through a pressure washer. Dilute hydrochloric acid at a ratio of 3 tablespoons to 1 gallon of water, and scrub the slab thoroughly with it, before spraying again with pure water through the pressure washer. Attach metal dividers to the grooves, and put plywood strips around the barrier of the floor if desired.
Mix Portland quick-dry cement with marble chips, using a ratio of one standard bag of cement (94 pounds) to 200-220 pounds of marble chips. Put them in a cement mixer, or mix them in a wheelbarrow. Read the instructions on the cement packaging regarding the proper amount of water for that product. Apply the mixture to the floor, spreading it with a floor roller. Press the terrazzo mixture down with a trowel to ensure an even layering. Check with the level to ensure that your surface is flat. Add more marble chips to give a loose scattering, and use the roller again to give the mix a tight pack and drive air bubbles out.
Let the terrazzo blend cure for two days, and polish the floor with a stone floor grinder. Begin with the coarsest grinder, and move gradually to the finer ones, hitting each section of the floor with each grade of stone. Stop when you see a visible shine all over the marble. Spray again with the pressure washer to clean away dust. Look for small holes appearing on the surface of the floor; these are signs of air bubbles. Apply a slurry of cement and water (following the manufacturer's instructions for the ratio), spread thin to cover the holes. Scrape away any excess cement with a trowel. Give two more days to cure, and then polish with the floor grinder at its finest level to give a shine to the floor.