Painting an interior brick wall is a good way to change a wall's appearance you may not like. Although it will likely be more challenging than painting a smoother surface, you can do it if you have patience and the right tools.
Clean and Repair
Before applying primer or paint, remove loose mortar or brick pieces. Fill holes and cracks, then sand the filler until it's smooth.
Apply Primer and Paint
Apply a primer with a lamb’s wool roller. Exterior latex will stick better to your brick. When dry, apply acrylic paint with a roller for the surfaces and use a brush for mortar joints.