When you are endeavoring on plastering a concrete wall you should know that it does acquire time. Plastering a concrete wall though can in fact change its appearance, make it more moisture resistant, add texture and level the concrete wall. The surface must be prepared correctly before the plastering. If this is not finished then the plaster can actually start to fall off.
When you are plastering a concrete wall you need a sandblaster, metal lath, 7 or 8 inch concrete screws, caulk, mold and mildew killer, wire brush, bonding agent, masonry sand, Portland cement, plaster and a trowel.
The first step in plastering a concrete wall is to prepare the wall. All paint that is peeling and flaking needs to be taken off using the sandblaster. If you do not wish to sandblast then attach the metal lath over the painted concrete wall. You must use the 7/8 inches screws and washers that are spaced 12 inches apart to attach the metal lath to the wall.
If they are cracks in the wall then you require to caulk them. If there is mold or mildew you need to kill this and remove the mold stains. With the wire brush you need to clean the mortar joints.
You need to mix I part of Portland cement and 1 to 2 parts of the masonry sand. You will then add water to this so that it is mixed together to a runny state. Cover the whole wall to about 1/8 inch of thickness with a dash brush. This coat will then need to be left for a day to dry and forms the base coat.
Now for the plastering which you will mix as stated by the manufacturer. Over the dash coat add a base coat with the plaster that is about ΒΌ to 3/8 inch thick. You apply the plastering with a trowel. If you want a flat look then you need to smooth it. If you want that textured look and feel then leave it how it is. Let the plastering base coat dry.
When it is dry you can then use the same plastering mix and technique to apply your second plastering coat.
That is it, your concrete wall has now been plastered, but it is a long process.