You can make a variety of building materials that are cheaper than the concrete version. They set quickly and are very strong. Depending on the mould, you can make floor or paving tiles or even bricks for walls. They also make good rainwater harvesters: being non-water absorbent, the risk of dew, algae and fungus is almost eliminated, and this ensures clean water. You can add colorants such as iron to make red tiles. Bricks are made with this technique make good insulation, keeping you warm in winter and cool in summer. The sand in the tiles acts as a fire retardant. if there is a fire, the outer layer of plastic melts, leaving a face of sand. Sand is not flammable, so it slows the spread of the fire through the brick never light a fire directly on top of plastic floor tiles. Plastic tiles are not advisable for roofing in case of fire