How to Paint Over Painted Brick
- 1). Clean any dirt from the brick wall with a pressure washer set to 1600 psi. Hold the nozzle about 6 inches from the wall and apply the water using a back and forth motion to remove any dirt or loose paint from the bricks. Allow the bricks to dry for two hours.
- 2). Put on a face mask and safety goggles. Remove any flaking paint from the wall with a putty knife. Sand the edges of the paint around the bare areas with the medium-grit sandpaper attached to a sanding block. Sweep up and bag the removed paint from the ground. Wash the wall with water from a garden hose to remove any residue left from sanding the paint. Allow an additional two hours of drying time.
- 3). Remove any loose mortar from between the bricks with a chisel. Replace with new mortar, using the putty knife to push the new mortar into place. Fill any cracks in the bricks with elastomeric caulking to prevent water seepage through the bricks and beneath the paint. If the cracks are greater than 1/4 inch in width, fill the crack with a foam backing rod and polyurethane caulking. Allow the mortar and caulking a full night to set before painting.
- 4). Place masking tape along any surfaces bordering the brick wall and lay dropcloths along the brick wall base.
- 5). Brush the edges of the wall with an acrylic masonry primer. Mix the primer with a wooden stir stick to create a consistent liquid throughout. Use the brush to create a 3-inch-wide stripe around the wall edges that the paint roller can overlap. This will make certain that you have an even coverage of primer up to the very edges of the brick surface.
- 6). Pour the primer into a paint roller tray. Use a 1-inch paint roller cover to roll the paint over the rest of the wall. Work from the painted edge inward, using the wet paint on the edge to help avoid lines between the edge and the rest of the brick wall. Overlap the rolled lines of paint on the wall to keep the look of the coverage consistent. Allow the layer of primer two to three hours to dry, then examine to see whether the old paint is still visible. If so, place a second layer of primer over the brick surface and allow it to dry. Using a paintbrush, go over any areas not covered by the roller.
- 7). Cover the primed surface with an exterior acrylic topcoat in your chosen color. Use the same application process used with the primer, adding layers as needed until you conceal the primer. Allow the paint to dry overnight.
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