Micro (design) Concrete is not well known in the UK but it is very popular in France. It is a mixture of Portland cement, silica sand, polymer resins with natural pigment added to provide colour. It is waterproof, unique, thin and flexible and can be applied to interior and exterior floors, walls, bathrooms, kitchens, worktops even swimming pools. Available in a wide selection of colours. Design concrete is versatile and hard-wearing.