How to Paint Discolored Concrete
- 1). Vacuum the floors to remove all dirt and debris. Anything left behind will scratch the floors during grinding.
- 2). Open windows or doors for ventilation if the concrete floor is inside your home. Cover all air vents with plastic sheeting to prevent dust from travelling through your house.
- 3). Put on a mask and goggles. Attach a diamond sanding pad to the grinder. Turn the grinder on.
- 4). Lower the grinder slowly to the floor and begin moving across the floor. Sand the entire area. Hold the grinder over the discolored areas and attempt to remove the stains. You might not be able to remove deep stains. Deep stains will be covered by the paint.
- 5). Vacuum to remove the sanding dust. Dampen a towel and run it across the floors to remove any small particles of sanding dust.
- 6). Tape the walls and anything else you don’t wish to paint.
- 7). Dip a brush into concrete and masonry paint. Paint the perimeter of the room. Cut in about 3 inches.
- 8). Pour concrete and masonry paint into a paint pan. Roll a long handled brush through the paint, removing the excess paint from the roller. Roll the paint across the floor in a thin layer. Let the first coat dry. Apply a second coat using the same method. Let the second coat dry overnight.
- 9). Roll concrete sealer on the floors to protect the paint. Apply two coats of sealer.
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