Water Repellent Block

Our water repellent concrete masonry units are manufactured with the MasterPel 240 (formerly Rheopel Plus) water-repellent admixture system. Specially formulated for use in the manufacture of concrete masonry units, the admixture is integrally mixed into CMUs during manufacturing. MasterPel 240 is in compliance with ASTM E514.


Note: Because water repellent blocks will not absorb any free water, the use of self-consolidating grout or a water reducer is strongly recommended.

The MasterPel 240 System is able to improve the quality, value, and overall aesthetics of concrete masonry construction through its several inherent benefits:

  • Optimizes overall water-repellent properties
  • Maintains excellent wind-driven rain resistance
  • Provides lasting protection from moisture damage without the use of exterior post-applied sealers
  • Enhances color intensity and uniformity
  • Reduces the potential for efflorescence
  • Improves the texture and consistency of manufactured concrete products
  • Increases the coverage rate of post-applied paints and coatings

MasterPel 240 is also available as an additive for masonry mortar mixes. Please visit our Accessories page for more information about MasterPel 240MA.