How to Paint Masonite Walls

Spread drop cloths over the flooring and furniture. Tape around the outer edges of the Masonite wall and the ceiling with painter's tape. Also apply painter's tape around all elements such as light fixtures and baseboards that will not be painted.

Scrape and sand any peeling paint or damaged areas on a previously painted Masonite wall. It is not necessary to sand unfinished surfaces unless the Masonite has sun or water damage.

Fill nail holes and any small damaged areas with caulk or spackling paste. Allow the caulk to dry completely before priming and painting the wall.

Roll a coat of water-repellent preservative over unfinished Masonite. Use a paintbrush in corners and along edges. If the Masonite has not been installed on the walls, apply preservative to all edges. Allow the preservative to dry according to the manufacturer's directions.

Apply two coats of primer to the Masonite wall, allowing drying time between coats per the manufacturer's directions. Use a roller made for a smooth surfaces. Touch up around the edges with a paintbrush.

Roll a coat of a good-quality latex paint over the entire wall. Allow the paint to dry, then add a second coat.