Painted and pre-primed surfaces: Test if surface is sound (refer to surface test below). Ensure surfaces are clean and stains are removed as much as possible by washing down with Selleys® Original Sugar Soap, using a scourer for any tough stains. Scrape off all loose and flaking paint then fill any cracks or holes with a suitable filler. Sand the filled areas and any rough surfaces to a smooth finish. Dust off. For very glossy surfaces, sand to a dull finish using 240 grit sandpaper. For pre-primed surfaces, contact Dulux Help & Advice. For chalky surfaces, sand back to a strongly bound surface and dust off. Timber: Fill nail holes with a suitable flexible wood filler. Sand the surface to reflect the final finish you desire. Sand any raised wood fibres to a smooth finish. For very dark, tannin rich timbers, use Dulux 1Step® Oil-Based Primer, Sealer & Undercoat. For pre-treated timber, check with the timber manufacturer for preparation and painting guidelines. Galvanised iron and ZINCALUME®: Clean with Selleys® Original Sugar Soap to remove grease and dust. Thoroughly wash off with water and allow to dry. Brick, masonry, fibro and fibre cement board: Freshly laid masonry and cement-based surfaces should be left to cure for minimum 28 days before painting. Ensure surface is sound and clear of any loose sand or cement. Wash down with water using a stiff brush to remove all loose material. Fill holes with grouting cement. To remove any efflorescence (white salts) wipe down with a 5% solution of acetic acid (white vinegar). Surface Test: Ensure surface is sound by cutting a small X through the existing paint with a sharp blade, press cellulose tape firmly across the cut and then rip off the tape. If the paint comes off, it is unsound and should be removed. Repeat at random in a number of areas, to test the surface. Check to see if there is any mould on the surface. If so, wash with a bleach solution (one part bleach, three parts water) or de-mossing chemical to remove mould or moss. Then wash with water. Refer to Dulux Help & Advice for further advice on surface preparation and product details.