Many types of repair work suggest that surface preparation is preliminarily performed. Best in this case, if plaster is used. Such material requires a certain specificity of circulation, so it is necessary to understand how it is applied.
You can apply plaster on the surface from various materials. Depending on what features the base has for plaster, the preparation of the surface will have a certain specificity. Attention is paid to how rough it is, and also whether the pores are present in its structure or not.
Porous surfaces must be treated with a primer before they are plastered. This is necessary in order to subsequently put the plaster too quickly to lose moisture. If this happens, then its drying will be uneven. As a result, the material will begin to crumble quickly.
If the surface is too smooth, it needs to be fabbed or not to apply notes on it with an ax. The most important thing is that the base is not too badly damaged. Otherwise it will be difficult to plastering it. But the base should not be made excessively smooth, because otherwise it will not work to cover it with high quality.