The functions of smoothing are to protect, beautify and leveling the surface.
By definition, preliminary skim coating is a layer of preparation for the next decoration that connect it with the substrate. Preliminary skim coating must have mechanical, physical and chemical properties very similar to the support and compatible with the finishing material.
The elastic modulus of preliminary skim coating will be less than that of the substrate but greater than that of the finishing.
The transpiring power of the layer of preliminary skim coating will be less of the topcoat but should be greater than the support.
CHEMICAL CHARACTERISTICS RELATED WITH SUPPORT
Mineral plasters only for mineral surfaces. Synthetic plasters only on mineral synthetic support.
CHEMICAL CHARACTERISTICS IN CONNECTION WITH FINISHINGS
The mineral plasters are suitable for mineral or synthetic finishings. The synthetic plasters are suitable only for synthetic finishings.