Rapid Setting Water Plugging Mortar


Fastfill WP is a rapid setting, polymer modified cementitious water plugging mortar for arresting water seepage and infiltration under pressure through cracks, joints and voids in concrete and masonry. Fastfill WP can also be used for rapid sealing and jointing in and around pipework, or in water retaining structures.

Fastfill WP is a single component, polymer modified, fibre reinforced, Portland cement-based water plugging and sealing compound. When mixed with water it exhibits unique hydraulic properties to produce a rapid setting mortar which can arrest water seepage and infiltration through joints, cracks or porous areas in concrete and masonry structures.


  • Pre-packaged material requiring mixing with clean water
  • Low shrinkage and high bond strength ensure monolithic performance and a watertight seal
  • Sets in 2 minutes at 20ºC, yielding a durable, high strength mortar
  • Physical properties of cured materials similar to base concrete
  • Polymer modified to ensure enhanced adhesion in jointing situations and prevent wash out
  • Non toxic when cured
  • No more hazardous to handle than ordinary Portland cement.

Specification Clause

The repair mortar shall be a single component, polymer modified, fibre reinforced, Portland cement-based plugging and sealing compound, which is physically and chemically compatible with the host concrete.

The cured repair mortar shall set in 2 minutes at 20°C, achieving a compressive strength of 4 MPa in 1 hour and 26 MPa in 28 days.

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Project Profiles

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