The next step that you can do is to wring the rag and then try to wipe down your walls.
Cleaning concrete prior to painting.
Pour dry dishwasher detergent or a concrete cleaning agent on the stain.
Let the detergent sit for 45 minutes then pour boiling water on the area and vigorously scrub the stained section with the broom.
Your supplies are likely to be a bucket scrub brush and detergent.
For many years it was a standard method of concrete preparation used by nearly all industrial commercial and institutional floor coating installers depending on the floor size and system to be installed.
Use a pressure washer to finish off remaining roots and dirt.
To make the best result in cleaning the concrete wall that is not already painted you also can add another bucket that you should fill with warm water.
Opening up a tight surface.
The bad news for the fastidious homeowner is that.
You want the surface to be as clean and bare as possible for the best coating of paint later on.
Remove efflorescence a white powder that.
For stubborn stains use muriatic acid in combination with your pressure washer set to at least 1200 psi.
Existing paint needs to be scraped and sanded.
Acid etching is the process of applying hydrochloric muriatic or buffered phosphoric acid to a slab then rinsing it off with water.
Mop the tsp solution onto the entire concrete floor using a sponge mop.
Prime and paint priming before you paint concrete floors helps ensure that your new look will stick.
Using a wet vacuum will dry the areas quickly without wetting the rest of the concrete.
Remove dirt and grease with trisodium phosphate 6 30 per quart concentrate or choose a more earth friendly.
Scrape any areas with loose or flaking paint and lightly sand using fine 120 grit sandpaper.
Hydrogen peroxide or ammonia also work well too.
Clean the concrete 1.
Yank off vines and moss growing on the foundation.
If oil happens to migrate to the surface darkening it before you can coat it it can be cleaned again dried and painted as soon as possible to allow the paint to dry before the stain reappears another time.
Prepare to mop the concrete with a trisodium phosphate solution tsp.
Scrub the surface with a long handled brush.