Preparation of the substrate for resins (with a roller)

Preparation begins with a careful analysis of the existing substrate : raw concrete, screed, old tiles, old resin coatings, self-leveling screeds. In each case, surface cohesion, absorption, presence of oils, greases, residues of glue or impregnating products, any rising damp, and structural cracks are assessed.

Concrete or screed floors often require mechanical treatment: sanding, shot blasting, or light scarifying, depending on the condition. The goal is to remove the weak surface, open the pores, and create a smooth surface for primers and resins to adhere to. Very smooth floors or floors with old, glossy paint require more thorough roughening.

In the presence of oils, greases, and contaminants (typical of garages or workshops), degreasing is essential. Alkaline detergents, repeated washing, thorough rinsing, and possibly mechanical cleaning help reduce contamination. If the oil has penetrated deeply, it may be necessary to remove a few millimeters of surface or use specific primers for "difficult" substrates.

Cracks and joints must be evaluated on a case-by-case basis. Shrinkage cracks can be resin-sealed or treated with elastic products, while structural joints must remain intact and not be "blocked" by resin. In many cases, elastic seals are applied or the joints are properly repaired before applying the finishing cycle.

For tiled substrates, preparation involves checking their adhesion, replacing any loose tiles, thoroughly cleaning the joints, and mechanically roughening them, as well as using specific adhesion primers. The goal is to transform a smooth, compact surface into a bonding base for the resin.

The choice of primer is the final step in the preparation process: epoxy, acrylic, polyurethane, solvent-based or water-based, with or without fillers. It serves to consolidate the substrate, even out absorption, and create a chemical bridge between the base and subsequent coats. In some applications, quartz sand is sprinkled over the fresh primer to improve the adhesion of subsequent coats.

Careful preparation requires time and equipment, but it avoids the most feared problem in this type of work: seeing the resin peel off in a "film" after a few months, not due to the product, but to an unprepared support.