How to Repair Crumbling Painted Brick

Clean the brick surface with a power washer, using the water stream to remove all dirt and some of the loose pieces of brick and mortar. Test the washer against an unnoticeable section of the wall to make certain the setting used will not strip away the paint from the brick surface. If damage occurs, turn down the pressure until the paint is safe from removal.

Put on a pair of safety goggles to protect your eyes from flying pieces of brick and mortar.

Remove the damaged bricks from the brick surface with a chisel and hammer. Place the tip of the chisel onto the mortar where it meets the damaged brick and strike the chisel with the hammer to cut through the mortar to the base of the brick around its perimeter. Remove the brick from the surface, and then remove the remaining mortar that surrounded it. Remove any debris with a nylon brush. Use a trowel to spread premixed brick mortar along the base of the hole and then place a replacement brick into the old brick’s place. Fill in the joints surrounding the brick on the other three sides with a tuckpointing trowel. Continue replacing all of the crumbling bricks in the surface until the surface is once again solid and complete.

Use the chisel and hammer to remove any loosened mortar from the joints between still whole bricks. Chisel out the mortar to a depth of at least 1/2-inch.

Replace the mortar that you removed with the premixed mortar mix, packing the joints between the bricks with a tuckpointing trowel. Go over the joints after filling with a jointing tool containing a head with the same tooling shape as that used with the undamaged joints on the wall. Run the tool through the joints to scrape away enough mortar to leave the joints at the same level and shape as the undamaged joints surrounding them.

Allow the mortar to dry for about 10 days. Keep the mortar damp for the first three days by spraying it with a misting bottle filled with water.

Paint the bricks after the mortar dries with the same paint color used for the rest of the brick surface. Apply the paint with a brush to make certain you get the bricks and mortar joints as well. Use an exterior paint for outdoor brick surfaces for longevity, and to allow the paint surface to endure exposure to the elements for an extended amount of time. Allow the paint to dry for 48 hours before touching the surface.