How to Repaint Concrete Stain
- 1). Degloss the already stained surface with a sander. The new stain won't adhere properly to an existing stain, so the surface texture needs to be roughed slightly. Remove any flaking or loose stain with a wire brush. Sweep the entire surface clean.
- 2). Fill a plastic watering can with a concrete etcher solution. Apply the etcher to a small section of the floor at a time, and work it in with the broom. Clean each area with a pressure washer after five to 10 minutes, and then allow it to dry.
- 3). Place a strip of duct tape onto the etched surface. Lift it up and examine it for any dust or dirt particles. The floor needs to be completely clean before you apply the stain. Wash it again if the duct tape shows any residue.
- 4). Apply a concrete bonding primer to the floor. Allow it to dry for at least eight hours. Make sure that the concrete floor is completely dry, or the stain won't penetrate.
- 5). Roll the stain on with long, even strokes, going in one direction. Apply a single thin coat, working in sections. Wait 24 hours before deciding if a second coat is necessary.
- 6). Allow the stain to dry for at least 72 hours before subjecting it to heavy traffic and placing furniture.
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