General:

See general comments under “Cement Plaster”. Another factor to be taken into account in the case of skimmed plaster, in addition to age, is its texture. With patent plasters such as Glass-stone, Cretestone, other gypsum or keenes types, the surfaces are sometimes trowelled so smooth, compact and hard as to be an almost marble-like finish. Special care must be exercised in the choice of the correct primer coat, as there is often a layer of fine powder on these surfaces. Skimmed plasters are only used on interior walls.

Preparation:

New:
Remove dust, dirt, plaster splashes. Cut out cracks and imperfections, fill and sand smooth when dry.

Previously limewashed or distempered:
Remove to bare plaster. Cut out cracks and imperfections, fill and sand smooth when dry.

Previously oil, alkyd, P.V.A. or acrylic painted:
If the existing paint is in poor condition, remove by scraping or with Dekro Super Paint Stripper. Wash down with a suitable concentrated detergent, rinse and allow to dry. Cut out cracks and imperfections, fill and sand smooth when dry.

If the existing paint is in good condition, wash with sugar soap and water, a suitable concentrated detergent or suitable solvent to remove dirt, grease, wax polish or other contaminants. Abrade glossy surfaces to form a key for subsequent coats. Rinse and allow to dry.