To paint a concrete porch, vacuum and wash it, treat stains with muriatic acid, seal the concrete, paint it, and seal it again. This four-day project requires a vacuum, a pressure washer, a scrub brush, liquid soap, muriatic acid, protective equipment, two paint rollers, a paint tray, sealant and paint.
- Vacuum and rinse the porch
Vacuum the porch thoroughly. Put on safety goggles, and rinse the concrete with a power washer set to 3000 pounds per square inch.
- Scrub the porch
Scrub the porch with a stiff cleaning brush and liquid detergent. Rinse it with the power washer.
- Remove stains with muriatic acid
Put on long rubber gloves and a face mask. Apply muriatic acid to stained areas, and work it into the concrete with the cleaning brush. Rinse the porch with the power washer, and let it dry for 24 hours.
- Seal the concrete
Apply a coat of clear concrete sealant with a paint roller. Rinse the roller thoroughly, and let the sealant dry.
- Paint the concrete
Use a fresh paint roller to apply several thin coats of exterior paint. Let each coat dry for two to four hours before you apply the next.
- Cover the paint with additional sealant
Apply additional sealant with the roller you used for the first coat. Let the sealant dry for 24 hours.