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Durock™ CST™ Moisture Vapor Reducer

Penetrating concrete moisture barrier utilizing reactive chemistry

Key Documents & Design Files



USG Durock™ CST™ Moisture Vapor Reducer is a single component moisture mitigation system that reacts with concrete to create a permanent moisture barrier 2-4 mm below the surface.

Main Features

USG Durock™ CST™ Moisture Vapor Reducer contains moisture-responsive particles that swell and contract to help regulate moisture vapor transmission rates at the surface of concrete.
  • Effective at managing MVER up to 10 lbs. (ASTM F1869) and RH up to 99% (ASTM F2170)
  • Silicate-free penetrating concrete moisture barrier
  • Moisture-responsive particles help create a permanent membrane 2-4 mm below the surface
  • Maintains a consistent pH at the surface level
  • Maintains surface profile for optimal bond of patching and leveling compounds and coatings
  • Dries in as little as 1 hour
  • Can be applied 24 hours after concrete is poured



Durock™ Brand CST™ Product Demo Video

Documents & Files

Data Sheets & Specifications

Data/Submittal Sheet (English) PDF 352.6 KB

White Papers

Sell Sheet (English) PDF 341.0 KB

Catalogs & Brochures

Brochure (English)
Brochure (Spanish) PDF 1.6 MB

SDS, Certifications & Reports

SDS (English) PDF 121.8 KB
SDS (Spanish) PDF 123.5 KB

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