Surface must be dry and clean. For new surface remove all loose powderly by sweeping with sand paper. Apply a sealing coat with No 1 National Exterior putty. Allow the filler to dry overnight before painting with emulsion paint. For old surfaces, necessary repair work of cracks and defective rendering should be done before painting, Remove all moss, Remove poorly adhering or powder coating. Apply sand paper to get smooth surface. For best results apply one or two coats of No 1 National Acrylic Primer or Exterior Filling.