Please login with your username and password.


Can’t remember your accounts password?

Can't access your account?

Select your language

This page is available in the following languages:

    Please select your location

    ​MasterCast 355

    Powder Admixture for Improved Water Resistance in Mortar & Concrete​


    MasterCast 355 reduces passage of water through concrete and mortar. It considerably reduces water absorption. By a physical action MasterCast 355 seals the surface of the mortar/concrete, producing a low permeability system. The hydrophobic ingredient of MasterCast 355 is insoluble in water and therefore becomes a permanent constituent of hardened concrete.

     MasterCast 355 also contains an airentraining plasticiser which allows a reduction to be made in the water content of the mix whilst maintaining workability and the final strength of the concrete or mortar. MasterCast 355 does not adversely affect setting time.


    • To pre-cast concrete and constructred stone products.
    • To reduce water ingress in in-situ concrete and cement rendering


    MasterCast 355 disperses rapidly upon contact with the mixing water distributing itself throughout the mix.

    • Hydrophobic element is insoluble in water.

    • Becomes a permanent constituent of the hardened concrete and cannot evaporate or deteriorate.

    • Does not change the setting time of cement, reduce strength of concrete or corrode reinforcement.

    • Has no chemical reaction. Its action is physical and positive and is thus permanent.

    • Reduced labour costs.

    • Water permeability and absorption is reduced, hence it prevents movement that can arise from intermittent wetting with a resultant reduction in surface crazing.

    • Reconstructed stone work stays cleaner longer and has greater resistance to attack from atmospheric acids.​

    Info & price request

    MB Construction Chemicals Solutions South Africa (Pty) Ltd



    MasterCast 355 TDS

    pdf (95,47 Kb)