How to Paint or Stain Old Concrete
- 1). Thoroughly clean the concrete to remove standing dirt and debris. Spray the surface with concrete cleanser and scrub with a hard-bristled push broom. Rinse with a power sprayer.
- 2). Repair any cracks, holes, or damage with concrete patching compound and a trowel. Smooth the surface of any repairs with the trowel. All the patched concrete to set according to times dictated on the packaging.
- 3). Sand the surface of the concrete using a floor sander and a 100-grit, screen-mesh sandpaper disc. Work in concentric circles until the surface of the concrete has been abraded sufficiently to remove any stains or discolorations. Clean the concrete a second time.
- 4). Spray stain over the surface of the concrete with a pump sprayer rated for acids. Hold the nozzle approximately 12 inches from the surface of the concrete and move the sprayer in broad arcs to obtain an even coat over the surface. Scrub the chemical into the concrete with a hard-bristled push broom. Allow the stain to dry according to times listed on the container before applying a second or third coat.
- 5). Paint the concrete as desired with a paint roller and paint bucket. Concrete paint is specially designed to grip to the surface of concrete but applies just like normal wall paint.
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