SILRES® BS 375

• Construction Materials
• Hydrophobic Impregnation
• Impregnation of New and Existing Buildings
• Pre-Impregnation of Construction Materials

Hydrophobic impregnation / priming

• The dilute solution of SILRES BS 375, whether it is being used to impregnate or prime, is either brushed onto the building material of applied by flooding. It is usually sufficient to treat the building material twice, applying SILRES® BS 375 solution liberally and uniformly, wet-on-wet. Best results are obtained by flooding the building material.
• To achieve good penetration of the impregnating agent/primer, the building material should be air-dry at the surface (to a depth of 5 mm). The area for treatment should not have any damp patches.
• The amount of hydrophobic impregnating agent / primer required for two liberal applications depends on the absorbency of the respective building material.
• The following examples demonstrate this:
  • Mineral plaster 0.5 to 0.8 l/m²
  • Brick masonry 0.4 to 2.0 l/m²
  • Aerated concrete 0.5 to 2.0 l/m²
  • Natural stone 0.1 to 2.0 l/m²
• When material requirements are being calculated for a bill of quantities, a sufficient large (1-2 m²) test area should be used to determine the amount of impregnating agent/primer needed. The efficiency of the treatment can also be checked on the test area.

Dilution

SILRES® BS 375 can be diluted with aliphatic or aromatic hydrocarbons or with anhydrous alcohol. We would recommend the use of petroleum hydrocarbons such as White Spirit 130/175 and White Spirit 145/200 or hydrocarbons with a low aromatic content, example Shellsol T. Alcohols should only be used as diluent of the impregnating agent is likely to come into contact with plastics that are attacked by solvent (foamed polystyrene, bitumen, etc.), and this cannot be avoided. The solvent used should have a boiling range of 140-190°C and an evaporation number of 30-90. If the above mentioned hydro carbons are used, SILRES® BS 375 sould be diluted in a weight ratio of 1:11 to 1:15.