Moisture and mold adhesion
It often happens having to whiten that small or large parts of the underlying paint tend to detach.
This phenomenon can be caused by three factors:
- In the case of inadequacy the paint on which it is whitening has not taken hold and tends to detach itself from the substratum due to dirt or poor quality of the varnish or its application.
- In the case of humidity , because the water infiltrated into the walls due to rising damp, rainwater percolation or other tend to detach the paint, in this case it is important to eliminate first the cause of moisture, then remove the incoherent portions of paint and only then repaint the surfaces.
- In the case of molds instead you have to brush the surface with a stiff brush, then apply a specific product and then paint.
Blockers: first bleaching or on bright colors
There are on the market products called blockers whose function is to limit the absorption of paint by the walls.
These are in fact in the case of new whitewashing on virgin walls or should be applied on walls colored by cigarette smoke or on particularly bright colors.