How to Repaint a Cinder Block Stairway That Has Mold & Mildew
- 1). Pressure wash the surface with a 2500 psi or greater pressure washer. Hold the pressure washer 12 inches from the block surface and use a 15-degree tip to remove paint and debris.
- 2). Remove all remaining debris and peeling paint from the face of the block using a paint scraper and wire brush.
- 3). Prepare a mixture of warm water and bleach using a formula of one cup of bleach for every three cups of warm water. Use the bleach water mixture to thoroughly clean all mold and mildew from the block surface. If the stains are particularly resistant to cleaning, spray a bleach mixture directly on the block surface and soak for 10 to 15 minutes. Scrub the stains away with a wire brush or stiff cleaning brush.
- 4). Clean any remaining oil or grease deposits with a solution of TSP, mixed according to manufacturer's directions, and a wire brush. Allow to dry.
- 5). Paint the block with a stain-blocking primer. Pitted block surfaces will require nearly double the amount of primer, so apply liberally. Do not skimp on the primer application. Use a sealing primer if the mold and mildew condition is likely to return.
- 6). Allow to dry according to manufacturer's instructions.
- 7). Caulk the joints where the stairway meets the wall, floor, doorway, window and any other structure that creates a joint between the block surface and structure surface.
- 8). Paint the block with the desired color of paint. Apply a second coat and allow to dry.
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