MasterSeal 550 - An acrylic reinforced, cement-based, flexible waterproof coating

Formerly MasterSeal 550M


MasterSeal 550 is a two-component, acrylic modified cement-based coating that requires only on-site mixing forming the ideal product to waterproof and resurface concrete, masonry, and most other construction materials. Simply applied by stiff brush, roller or trowel, it forms a waterproof, flexible coating. 

MasterSeal 550 provides an effective barrier to waterborne salts and atmospheric gases. Fluid applied, MasterSeal 550 provides a hardwearing, seamless, waterproof membrane for roofs and foundation protection.

Where is MasterSeal 550 applied?

  • To reface and even out variations in concrete surfaces 
  • As a waterproof lining for water retaining structures like water tanks, pools, reservoires, etc. 
  • For coating seawater channels 
  • Sealing and coating tie bar holes to ensure water tightness 
  • For waterproofing and protection against brackish water 
  • To provide foundation & retaining walls protection 
  • As a waterproof coating for roofs 
  • 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 550?

  • A 1mm coating provides anti-carbonation cover equivalent to over 80cm of concrete 
  • Waterproof – resists up to 7 Bars (70 metre head) of pressure 
  • Excellent adhesion – bonds to porous and non-porous surfaces 
  • Flexible 
  • Non-toxic – suitable for contact with potable water 
  • Suitable for light pedestrian traffic 
  • Breathable - whilst repelling water, allows substrate to breathe 
  • High resistance to carbon dioxide and chloride ion diffusion 
  • Unlike conventional coatings, which require a 7-28 day cure of concrete, MasterSeal 550 can be applied to 24 hourold concrete, thereby giving immediate protection

Product Information

Technical Data Sheet


MasterSeal 550 5KG (Part B) MSDS

pdf (162,99 Kb)

MasterSeal 550 TDS

pdf (215,69 Kb)

MasterSeal 550 grey (Part A) MSDS

pdf (215,87 Kb)