Tips for Painting Cinder Block

[SavvyCat]

I have a cinder block wall around my back that is a reddish terra cotta color. The bottom three rows were painted a matching color to hide staining from mildew. I was told that comes from the house behind me being a higher elevation. There are a few places where it looks like salts are penetrating, and some random mildew, and I was thinking about painting the entire wall in a light color.

What is the best way to prep the wall, and what paint should be used? I'm wondering if a good coating a Kilz is in order, or maybe a sealer of some sort. I would appreciate some tips on such a project.

 

[slownsteady]

It sounds like you are talking about an outside wall, but you should confirm that. A good wire brushing should remove any loose paint and dirt and grit. I recently picked up one to fit my angle grinder and that worked well. A good masonry paint should work well, but I can see the point in some kind of sealer, maybe Thoroseal.

 

[nealtw]

efflorescence is stuff washing out of the block with water coming thru. Mold or mildow will grow on dust, and pollen.
Keeping it clean would help, sealing in moisture would not.
Breathable paint for brick and concrete.