MasterSeal 521 - A polymer modified cementitious, durable, waterproof coating


MasterSeal 521 is a two-component, polymer modified, cementitious coating that requires only on-site mixing to form the ideal product to provide a durable, waterproof coating to re-surface concrete, masonry, and most other construction materials. 

MasterSeal 521 imparts the natural concrete appearance.

Where is MasterSeal 521 applied?

  • To re-face and even out variations in concrete surfaces 
  • As a waterproof coating for water-retaining structures like water tanks, pols, resevoires etc.
  • To provide foundation protection 
  • As a backing to marble and granite to prevent water ingress, and thus alleviate surface staining 
  • To provide protection to concrete surfaces from carbonation and chloride attack For use on pedestrian walkways in marine areas 

What are the advantages of MasterSeal 521?

  • Excellent adhesion – bonds to porous and non-porous surfaces 
  • Limited flexibility 
  • Suitable for light pedestrian traffic
  • Breathable – whilst repelling water, allows substrate to breathe 
  • Slurry or trowelable consistency; application is still possible by spray Unlike conventional coatings, which require a 7-28 day cure of concrete
  • MasterSeal 521 can be applied to 24 hour-old concrete, thereby giving immediate protection 

Product Information

Technical Data Sheet


MasterSeal 521 TDS

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