Before applying Grancoryl paint, all surfaces must be sound, clean, dry and free from grease. If mould or algae are present, treat with Fungicidal wash, remove with a scraper of stiff brush, then treat the surface again with Fungicidal Wash. Any lime wash, distemper or flaking paint should be completely removed. Chalky underbound surfaces should be dry brushed and treated with Stabilising solution as directed.