New walls can look stark and uninviting. While some interior walls offer smooth surfaces for easy painting, rendered walls have a layer of stucco over the underlying brick or wood surface. While many homeowners choose to leave their newly rendered walls unpainted, applying a coat of colour will help protect the surface and provide a finished look.
Allow adequate time for your newly rendered walls to cure. According to Ask the Builder, new stucco requires about 90 days for the damp rendering to cure. Painting too early may cause your paint to blister and peel.
Wash your walls with a cellulose sponge and a little dishwashing detergent mixed in warm water. Although your newly rendered walls may appear clean, invisible fingerprints can keep your paint from adhering correctly. Rinse the soap residue from your walls with clean water. Let your walls dry for 24 hours.
Clean your walls with a tack cloth to remove small particles of lint, dust and cobwebs. Gently pat the tack cloth over the surface of your walls. Avoid rubbing or scrubbing your stucco finish.
Place painter's tape on the areas surrounding your stucco walls, such as the ceiling, adjoining walls, doorways and trim. Lay plastic sheeting or dust sheets over your floors and furniture to protect these items from paint damage.
Apply a primer coat to your walls. Select a primer formulated for use on stucco finishes. Brush the primer around your windows, doors and other objects. Use a paint roller with a nap thickness of 1 1/2 inches. Spread the primer over your walls with your roller, using a horizontal zigzag and following with a vertical zigzag, covering the entire surface of your walls. Let the primer dry for the recommended amount of time specified on the label. Depending on your particular product, you may need to let the wall set for 12 to 24 hours.
Apply your colour coat over your primer. Although satin and semigloss finishes provide easy care and clean up, too much sheen may make your textured wall overwhelm your room. Consider using a flat paint to enhance the thick texture and pattern of your rendered walls. Brush your colour against the edges of your walls and openings, creating a width of about 4 to 6 inches along borders. Overlap the outer 2 to 3 inches of the brushed border with your paint roller to create a good seal. Allow the first coat to dry, and then follow with a second coat.