Farrow & Ball Wall & Ceiling Primer & Undercoat is an easy-to-apply base for interior walls and ceilings. It's designed to minimise imperfections for a smooth and even finish, helping to enhance the appearance, adhesion, and longevity of your chosen wall colour. Follow with Farrow & Ball Estate Emulsion or Modern Emulsion for a rich depth of colour. Dilute on new plaster with up to 20% water.