Clean the concrete thoroughly with trisodium phosphate tsp and warm water then let dry.
How to repaint concrete wall.
Seal the concrete wall.
Use patching compound to fill any holes scratches or gouges in the concrete surface.
In case of mildew infestation treat with a bleach solution 1 3 laundry bleach to water respectively by swabbing or brushing.
Place a piece of plastic food wrap on the surface and leave it for 24 hours.
Get complete coverage and make sure your sealer is completely dry before moving on to the next step.
Step 1 cleaning and scrape.
Scrape any areas with loose or flaking paint and lightly sand using fine 120 grit sandpaper.
Apply wide painter s tape to the wall where it meets the floor to avoid painting the wall.
Again follow the manufacturer s instructions to confirm the necessary application and drying time.
Before adding your color you need to use primer to ensure that the paint will stick.
Use a masonry or concrete sealant to seal the wall.
Try krud kutter concrete clean etch 8 50 for 32 ounces.
Concrete sealer prevents water from absorbing into the concrete and helps prevent stains.
Get as much ventilation in the room as possible.
Remove efflorescence a white powder that forms on moist concrete.
Apply a primer to the concrete to ensure strong adhesion of the paint.
If the concrete has not been sealed there will be condensation on the plastic wrap.
Check to see if the concrete has been sealed.
Apply 1 layer of concrete paint primer with a paint roller.
Roll on 1 coat of concrete sealer and allow it to dry overnight.
If you need more cleaning muscle try phosphoric acid masonry cleaner 27 per gallon.
Prepare a solution of water mixed with any household cleaning chemical.
Wash the wall with tsp and let dry thoroughly.
Existing paint needs to be scraped and sanded.
You may need to wait several days.
Concrete sealer is available at most hardware or home improvement stores.
Fix any cracks with a concrete crack injection kit.
You ll paint this sealant onto the concrete in long even strokes.
Scrub the surface with a long handled brush.
For repainting concrete with chalky old paint use boysen chalk blocker b 7304 as surface conditioner.