SILRES® BS 34 A is a stable, low VOC silicone and organic polymer containing water based emulsion. When applied to a surface it forms a stable, penetrating water repellent for enhancing a wide variety of porous mineral substrates including concrete, natural and artificial stone and unglazed ceramic tile.

SILRES® BS 34 A is not recommended for below grade applications where hydrostatic pressure can be significant.


  • Provides excellent water repellency to reduce cracking, spalling, freeze/thaw damage, chemical degradation, efflorescence, and dirt pickup, thereby lengthening substrate life and reducing maintenance costs.
  • Enhances the features of the substrate providing a vibrant appearance
  • Repels water, hindering penetration, maintaining a consistent appearance
  • Beads liquids
  • Very low VOC
  • Physically and chemically bonds to substrates increasing the service life, making cleaning easier, thereby reducing maintenance costs
  • Improved UV stability
  • Suitable for interior or exterior decorative stone and concrete projects

Surface preparation
Surface preparation depends on substrate placement, type and strength, curing and finishing processes, age, condition, previous contamination, and the presence of previous coatings. Surfaces should be clean from dust, dirt, oils, grease, curing compounds, other coatings, efflorescence, and laitance before applying SILRES® BS 34 A.

Cleaning methods which are compatible with the application of SILRES® BS 34 A include:

  • Mechanical: abrasive blasting (sand, baking soda, vacuum).
  • Chemical: acid etching, stripping, solvent de-greasing, caustic soda scrubbing, alkaline soap scrubbing, high pressure washing, high pressure washing with sand.
  • Heat: propane and acetylene torching.


If strongly acidic or caustic cleaning agents are used, neutralize the surface and completely wash to remove any residues. Before using any surface preparation method, a test patch should be performed with the customer's approval to ensure desired results are achieved.

New concrete should be allowed to cure for at least 28 days before applying SILRES® BS 34 A. Substrate moisture level below 4% promotes penetration of product.

SILRES® BS 34 A is intended to be used at full strength or may be blended with water to desired ratio.

Mix before each use.

SILRES® BS 34 A emulsions can be applied by brush, sponge or roller. Multiple coats may be applied wet-on-wet.

Do not allow product to pool. Remove excess material before it cures.

Water and oil repellency starts to develop within 24 hours.

A test patch should be performed prior to general application with the customer’s approval to ensure that desired appearance, water and oil repellency are achieved. It is advisable to test the product on an inconspicuous area.

Surfaces treated with SILRES® BS 34 A should be cleaned as soon as they have been exposed to contaminant. Paint is very difficult to remove once it has completely cured.

Treated surfaces should be protected from contamination for 24 hours.


The "Best use before end date" of each batch is shown on the Certificate of Analysis. Storage beyond the date specified on the Certificate of Analysis does not necessarily mean that the product is no longer usable. In this case however, the properties required for the intended use must be checked for quality assurance reasons.

Sales and support

Wacker Chemical Corporation
3301 Sutton Road
Adrian, MI 49221-9397
United States
+1  888  922-5374 (Phone)

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