How to paint concrete walls.?

Question

I like in an apartment with concrete walls and I want to repaint my bedroom. The walls already have at least one coat of paint on them. What do I need to do to paint (primer, how many coats, type of paint, etc.).

Answer 1

If the existing paint is in good shape, all you really need to do is clean well and throw some paint on.

For cleaning, use TSP (Tri-Sodium Phosphate, any store with a decent paint department will have it) mixed in water, strongest solution listed in the directions.  Rinse -- you must rinse after TSP.  Let the walls dry completely.

As for the paint, look for something labeled 100% acrylic latex in your choice of finish.  I would stay away from flat -- more gloss gives you more durability.  More gloss also shows imperfections in the wall more, so normally I would stay away from gloss or semi-gloss and settle into a satin or eggshell finish.  Since concrete walls have a texture to them, you can do the semi-gloss without it looking bad if you like.

You will probably need two coats for this one.  The texture of concrete makes it difficult to cover all of the little voids in one coat unless you put it on much thicker than it should be.