New or Bare Surfaces: New or bare surfaces must be clean, dry and free from efflorescent salts. Remove all loose, defective or poorly adhering material by rubbing down using a suitable abrasive paper or stiff fibre brush and dust off. Treat any areas affected by mould, lichens, algae & moss with bleach. After priming new surfaces with Dulux Aqua Prime, fill the surface with Dulux Wall Putty. Apply primer on a wall putty before application of topcoat. Previously Painted Sound Surfaces: Remove all loose, defective or poorly adhering material by rubbing down using a suitable abrasive paper or stiff fibre brush and dust off. Spot prime and fill the surface as described above if required. Powdery, Dusty and Cracked Surfaces: Make good minor defects. For larger holes and cracks, use sand and cement mixture. Allow the surface to dry. Prepare surface as described above.