The surface must be dry, clean, free of grease, loose particles, dust, etc. Any existing cavities in concrete should be repaired in advance. The substrate is then primed as follows;
• Very absorbent surfaces: H95 IMPRIMATURA
• Concrete surfaces: R25 PRIMER W
• Surfaces with Bituminous membranes: BITUMPRIMER
• Asbestos surfaces: PRIMER PER RESINGUAINA
If the surface is not dry, the moisture within the substrate will generate vapour when exposed to sunlight which will then cause the formation of bubbles and a subsequent detachment of the coating.