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  • Efflorescence Blocker

    • Prevents Mineral and Alkali Staining
    •  Excellent Scratch and Stain resistance
    •  Resists Hot-Tire Pickup 
    •  Prevents costly construction repairs

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    EFFLORESCENCE BLOCKER® Material Warranty
    5 Yr Warranty Apply 1 Coat

    Product Overview  |  Technical Data
    Coverage Rates
      |  Application Guidelines

    1 Gal RTU


    5 Gal RTU


    Technical Documents




    Efflorescence Blocker is a versatile product designed to block and prevent efflorescence and alkali from rising to the surface of a porous substrate. It is ideal for applications where efflorescence is not preventable and is constantly being maintained. It is typically used on floors where waterproofing membranes have failed or were not installed or other applications where moisture penetration is unavoidable. The finish results in a natural appearance, with some substrates slightly darkening.


    • Blocks efflorescence and alkali from coming to the surface
    • Ideal for planters and groundwater penetration
    • Resist hot-tire pickup
    • Excellent exterior durability
    • Direct and reverse impact resistant
    • Works as a universal primer
    • Water and stain-resistant
    • Wet and dry adhesion

    Recommended Uses

    • Waterproof Membrane Failures
    • Water Repellent Sealers
    • Concrete Floors
    • Retaining Walls
    • Garden Stones and Pavers
    • Walkways
    • Sound Walls
    • High Alkali or Mineral Substrates
    • and more!

    Coverage Rates (Theoretical)

    Substrate Sq Ft / Gallon # of Coats*
    CMU (Precision Block) 60-70 1
    CMU (Split Face) 50-70 1
    CMU (Scored/Fluted) 65-80 1
    CMU (Lightweight) 40-55 1
    Clay Brick 125-150 1
    Stucco 100-150 1
    Dense Masonry Surfaces 125-150 1
    Wood 150-200 1
    Clay Block 50-60 1
    EIFS 80-120 1
    Concrete 125-150 1

    *Always apply material at the appropriate spread rates. Please see Technical Data Sheet for correct application instructions.

    How To Use

    1. Remove any current efflorescence.
    2. Allow the substrate to dry for 1-2 hours depending on the weather.
    3. Apply a saturation coat of Efflorescence Blocker using a  synthetic 3/4″ nap roller, a hand pump sprayer, or airless sprayer allowing it to penetrate as much as the substrate will allow. Backroll any drips or pooling. Do not atomize.
    4. Allow to dry for at least 1 hour. Cure time is 5-7 days.


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