Rockbond Admix 1305 (RB A1305)

Product Information Sheet:

ROCKBOND ADMIX 1305 (RB A1305) powder is a blend of special admixtures which has been formulated to retard the set of Portland cement based cementitious materials. The powder will increase the consistency life and will retard the early strength development of Portland cement renders, mortars and non flow concretes. The powder is ready to use, packaged in 25kg moisture proof, durable bags and has a shelf live of 2 years.

Special Properties

  • Can be packaged in water soluble bags for convenient handling.
  • Effective when either premixed with cement or quickly dispersed in the mix water.
  • Admix 1305 retards composite cements, including blends of Portland, microsilica, alumina, pulverized fuel ash and blastfurnace slag cements.
  • Will retard the early strength development of cement based materials at high temperatures.
  • Potent and efficient: can be used at low dosages.
  • High yielding, economical, non flammable, non toxic, odour free, user friendly and safe to use.


  • For applications where an increase in the workability life of mortars or non flow concretes are required.
  • To increase the time necessary to mix, pump or place mortars at 20ºC or more.
  • For use in hot climates or high temperature situations to prevent cementitious mixes from “going off” too quickly.
  • To retard the set of non flow cementitious materials.
  • For gunite and shotcrete spray applications in hot climates.
  • For use with ready mixed concrete which has to travel over long distances.