Skim Coat / Plaster Finish

A thin (2–3 mm) finishing coat of gypsum plaster applied over plasterboard or a base coat to create a smooth, flat surface ready for decorating. Skimming requires skill and experience to achieve an even, mark-free finish. Many extensions use a 'board-only' finish (taped and filled joints without skim) as a cost saving, though the quality is lower.