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webercem keycoat

Single-component polymer-modified, cementitious bonding aid and steel reinforcement primer. It requires only the addition of clean water to produce a bonding slurry for the webercem range of repair mortars, cementitious screeds, renders and new to old concrete.

Contains migrating corrosion inhibitor to protect the steel reinforcement within the repair zone and reduce the rate of corrosion within the vicinity of the repair.


  • To act as a holding primer for steel reinforcement prior to the application of repair materials.
  • To enhance the bond of cementitious repair mortars, renders and screeds to concrete.
  • Bonds new to old concrete.


  • High initial grab to improve the build of the repair mortar and promote the bond to the concrete.
  • Excellent adhesion to steel reinforcement.

This product has been formulated to comply with the requirements of BS EN 1504-3.

General information

Uniclass 2015

Pr_20_31_53_66 Polymer-modified cementitious slurriesPrimary


C42/315 Protective coating to reinforcement

Specification data - Polymer-modified cementitious slurries

Product Reference

webercem keycoat

Standard product features

Technical characteristics:

  • Mixed density: 1.9 kg/ L.
  • Typical coating thickness: 0.5–1 mm.
  • Bond strength to concrete (BS EN 1542): 1–2 N/ mm² dependent on substrate and repair mortar.