Bare plaster is a highly alkaline wall material. New plaster can also have a high moisture content, making it difficult to paint. It is necessary to apply an appropriate primer to bare plaster to protect the paint from the alkalinity of the material. Once you prime the plaster, you can apply any interior paint finish that best matches your decor. Always allow new plaster at least 30 days to completely dry before you paint it.
Lay dust sheets along the edges of the wall, or underneath the plaster item you want to paint.
Pour the 100 per cent acrylic primer into the paint tray. Roll a 3/8 inch nap paint roller into the paint tray to coat the roller completely. The short nap of this roller will prevent painting marks from being left on the wall as the paint dries.
Apply the primer to the bare plaster in even, vertical strokes from floor to ceiling. Overlap each stroke to eliminate the appearance of stroke edges. Apply the primer to the entire plaster surface and let it dry according to the directions on the package.
Rinse the paint tray and roller clean in the sink.
Stir the latex paint in your colour choice with a paint stirrer and pour it into the paint tray. Coat the paint roller with the paint.
Apply the paint in the same way you applied the primer, with even, vertical strokes that overlap. Let the paint dry for three hours, then apply a second coat. Let the second coat dry overnight.