Koster Repair Mortar Plus

repair mortar

Fast setting, expanding repair mortar

Koster Repair Mortar Plus is a watertight, fast setting, slightly expanding repair mortar with excellent adhesion (even to old building material substrates). With the addition of Koster SB Bonding Emulsion, it can be used as a PCC (polymer-modified cement concrete) mortar.

Repair Mortar Plus is intended for the execution of watertight repairs and touch ups.  It can be used for the installation of fillets in the wall/floor junctions which are exposed to pressurized water prior to the application of bitumen thick film sealants such as Koster Deuxan Professional and Deuxan 2C, and cementitious slurry systems such as Koster NB 1 Grey.

Repair Mortar Plus can be used for underfilling machine foundations as well as for filling blowholes, cracks, tie bolt holes and oversized joints.

  • Watertight
  • Fast Setting
  • Slightly expanding
  • Excellent adhesion
  • Can be applied to all mineral substrates
  • Suitable for watertight repairs and touch ups to substrates
  • Positive and negative side waterproofing
  • Can be used internally and externally on concrete, brickwork, blockwork or masonry
  • Easy application
  • Seamless application
  • Suitable for new construction and repair on existing structures
  • Suitable for waterproofing basements (exterior or interior horizontal and vertical surfaces)

Repair Mortar Plus is the perfect solution for:

  • Repairs to existing substrates
  • Repairs to concrete and screeds
  • Detailing to dry pack joints
  • Construction joint detailing
  • For patch Repairs
  • Filling tie bolt holes in concrete construction
  • Detailing around service penetrations

NBS Specification J10 Cementitious Mortar Tanking/Damp Proofing 340 Sealants

Ancillary Products

We recommend:


Wear protective gloves and goggles when processing the material. Observe all governmental, state and local safety regulations when processing the Repair Mortar Plus.

Substrate Surface

Ensure substrate surface is sound and clean, free of oil and grease prior to the application of Repair Mortar Plus. When installing mortars substrate preparation is of vital importance. Pre-wet all mineral substrates before the installation of Repair Mortar Plus.  The surface near pore structure must be saturated, (avoiding standing water and puddles) so that it does not absorb water from the applied mortar.

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Product code:DMS171

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