Mineral, highly flexible polymer-cement adhesive for bonding expanded (EPS) and extruded (XPS) polystyrene boards, for bonding graphite styrofoam and mineral wool (MW) boards, to various mineral substrates, as well as for embedding reinforcement mesh and leveling the entire facade surface. BK-StirolFix Special is used as an adhesive for bonding and as a base coat, i.e. adhesive for reinforcement within the Bekatherm Prestige thermal insulation system.

The substrate to which the adhesive is applied must be solid, clean, durable, free from efflorescence, oil residues. Smooth low-absorbent concrete, with residual dirt from the formwork, should be coated  with BK-BetonKontakt one day before bonding the boards. It is not necessary to apply a primer on new brick walls. In the case of bonding the panels to the walls of aerated concrete, coating with BK-Nivelator is recommended in accordance with the instruction manual. The preparation is performed by adding the powder in about 26-28% of water until complete homogenization. Leave the mass to rest for about 10 minutes and then stir again to obtain an adhesive of appropriate density. The prepared adhesive is applied to thermal insulation boards (along the entire perimeter of the board with the addition of three application points in the middle), and then the boards are bonded on the substrate by pressing. After min. 48 h perform anchoring with fasteners with a metal core, which is a mandatory step when using the system with MW. After anchoring, a very thin layer of adhesive should be applied on the entire surface of the board with a drying time of about 4 hours. When embedding the reinforcement mesh, the adhesive is applied on the entire surface of the board with a serrated trowel (tooth depth 8-10 mm). The reinforcement mesh (min. 10 cm of overlap between strips) is embedded into freshly applied adhesive. After drying, the entire surface is leveled with a new layer of adhesive. The total thickness of the adhesive finish should be 5-6 mm. The adhesive should be protected from premature drying and freezing. When bonding MW boards, the entire surface of the board should be coated with a thin layer of adhesive or at least the parts to which adhesive is applied. The adhesive is then applied over the entire perimeter of the MW board with the addition of three points in the middle. In further work, follow the same rules mentioned in the section on EPS boards bonding. See product datasheet for more detailed instructions.

Approximate material consumption: about 4-5 kg/m² for adhesion  and about 6-5 kg/m² for reinforcing

Under normal conditions, 24 hours of drying are required before grouting. Under normal conditions it takes 7 days for the surface to be fully functional