$SILRES<sup>®</sup> BS 1803 A

SILRES® BS 1803 A is a stable, VOC compliant, 60% active silicone emulsion for reducing water uptake and producing visual beading while not blocking pores or capillaries of concrete substrates. SILRES® BS 1803 A is found to be particularly effective in applications that require beading and water uptake prevention at very low addition levels.

Intended uses include: Admixture for non-load bearing cement-based formulated products such as pre-cast products, blocks and pavers 

Additional usage is as a topical sealer for post-treatment of cement based formulated products


  • Excellent water repellency: reducing cracking, spalling, freeze / thaw damage, chemical degradation, efflorescence and dirt pick-up
  • Excellent beading for improved aesthetics
  • Low VOC emissions during curing
  • Minimizes darkening effects, maintaining the original substrates’ appearance
  • Minimal effect on adhesion of topcoats to the mineral substrate, improving the service life of the paint
  • Lengthens substrate life, reducing maintenance costs

Use of SILRES® BS 1803 A as a waterproofing concrete admixture in accordance with ASTM C 494: SILRES® BS 1803 A can be diluted in the mix water, added simultaneously with the mix water or post added to the wet concrete blend. The recommended admixture range is 0.2-1.0% based on cement (3 oz. to 16 oz./cwt).

- We recommend testing compatibility with other concrete admixtures separately.

Use of SILRES® BS 1803 A as a topical waterproofing sealer (post-treatment): Recommended dilution is a 1:4 ratio of SILRES® BS 1803 A to water (by weight).

Recommended application rate is 125 ft² per gallon.

Product may be applied with a roller, brush or low pressure sprayer. DO NOT ATOMIZE THIS PRODUCT.


  • Thoroughly mix SILRES® BS 1803 A prior to use to insure that the emulsion is homogeneous.
  • Tap water is acceptable for blending. Due to the chemical variables in tap water and in concrete formulas it is recommended that samples be tested for water repellency, beading and other performance parameters prior to commercial use.
  • Mixing time should be adjusted to insure thorough distribution of all components including SILRES® BS 1803 A.
  • Depending on curing conditions, water repellency can be seen after 24 hours and maximum water repellency is realized in about 72 hours. Beading generally improves over time however best results are noticed after 28 days.


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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