With today's decorative overlay systems, it's easy to give almost any concrete surface, indoors or out, a complete face-lift. . Many of today's systems blend polymer resins with cement, sand, and other additives to improve performance, wear resistance, and aesthetic qualities. Polymer-modified overlays can be applied in layers as thin as a credit card or up to several inches thick.. They adhere well to existing concrete and resist damage from salt, chemicals, UV exposure, freeze-thaw conditions, and abrasion.