Concrete Surface Preparation

New concrete or masonry:
Must be allowed to cure at least 30 days before coating. The moisture content of the concrete/masonry should be less than 6%. In case of large areas and for severe exposure conditions, the surface has to be prepared by light blasting. In less critical areas where blasting is not practical, wire brushing has to be adopted to remove laitance, followed by treating with dilute hydrochloric acid (10%).

Old concrete surface:
Remove the surface contaminants like grease, oil, etc., by solvent wiping or by 10% caustic solution. Preferably the surface has to be prepared by light blasting. In case, blasting is not practical, etch the surface to get a good profile by treating white dilute hydrochloric acid (10%).Remove acid and contaminants by liberal wash with water. Ensure that acid solution does not retain on the surface and joints.