Contractors use a term called parging when applying a thin coat of mortar or concrete to a wall in order to protect and repair its surface from the effects of air voids or to improve the appearance of concrete block. The appearance then becomes like that of stucco.
Should you find yourself in need of parging a wall and wish to consider doing it yourself, there are a few things worth noting. You will need to have the proper tools for the application, which may be found in any hardware, home improvement, or lumber supply store. Portland cement, sand, and water are the ingredients used to create the parging mixture.
Here is how to apply parging to a wall.
Step 1 - Make Parging
In order to make the parging, you will need to mix Portland cement, sand, and water to a consistency you find easy to apply.
Step 2 - Clean the Wall
Dampen the wall surface with water.
Step 3 - Apply a Thin Layer
Using a trowel, apply a very thin layer of your mixture to the wall surface. Apply the mixture by overlapping strokes and using a sweeping curved motion.
The steps used above will create a surface that can be painted for a finished look.