We use Smooth surface for painting – When properly applied to walls, wall putty fills imperfections, cracks, and defects on the surface. Wall putty bases have an excellent affinity for concrete or plastered surfaces. Therefore, when applied to the exterior or interior walls of a house, the application of wall putty can create a smooth relaxation-free surface for a beautiful paint finish. wall putty is basically a white cement based fine powder that is created into a smooth mixture and applied to the walls before painting. It helps to clean the wall.