Things You'll Need
Trisodium phosphate (TSP) solution
Concrete walls in your home can be unsightly, especially when those walls are covered with faded or peeling paint. Perhaps the simplest way to cover old painted concrete walls is to remove the original paint from the walls and repaint or stain them. Covering painted concrete walls with a new coat of paint or stain is a fairly simple project that many homeowners can handle on their own.
Remove the old paint from the walls. Use a scraper to scrape as much as the paint off as possible and then go over the walls with a wire brush to remove any flakes of paint left behind.
Clean the concrete walls thoroughly with a trisodium phosphate solution and a scrub brush. The TSP solution will remove any grease and oil that is on the wall, which can prevent the paint from sticking. Rinse the wall well once it is clean and allow it several days to dry.
Fill any holes or cracks in the concrete wall. Use hydraulic cement, mixed according to the manufacturer's directions, and a putty knife to fill in the gaps.
Ensure that the walls are properly sealed and do not have any leaks. Test this by taping plastic sheets over all four walls of the room with duct tape around the edges so that each sheet is sealed down completely. Let the plastic remain on the walls overnight and check in the morning for condensation on the plastic. If there is no condensation, the walls are properly sealed.
Seal the walls if condensation does appear on the plastic during the condensation test. Concrete sealer can be applied with a paint roller and the corners should be filled in with a standard paint brush.
Apply fresh paint or concrete stain to the wall. Concrete stain acts much like paint, dying the surface of the concrete a different shade. Paint or stain can be applied with standard rollers and paintbrushes. Use thin layers of paint or stain and do at least two layers.