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  • Efflorescence Blocker ®

    Blocks efflorescence and alkali from coming to the surface
    Prevents Mineral and Alkali Staining. Ideal for planters and groundwater penetration.

    Excellent exterior durability
    Resists hot-tire pickup. Excellent scratch and stain resistance.

    Works as a universal primer
    Wet and dry adhesion. Water and stain-resistant. Prevents costly construction repairs.

    Efflorescence Blocker ®

    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. Please keep in mind, Efflorescence Blocker is a preventative — if the surface already has efflorescence staining, it will need to be removed first.

    Please Note: Current efflorescence staining will need to be removed first. Please see Restore-N-Prep

    Note to Specifier – CSI Reference Codes
    04 2 00 Exterior Stone, Cladding, Stone Masonry
    07 19 00 Acrylic, Silane Siloxane, Penetrating Polyester, Hybrid Water Repellents
    09 24/25 Cement Plastering

    Best Tools for Application

    Small Surfaces
    A foam brush is recommended to soak in and saturate your substrate.

    Medium Surfaces
    Use a small hand pump sprayer.

    Large Surfaces
    Use an airless sprayer with a spray tip size between .035mm to .051mm.

    Application Best Practices

    1) Step One: Prepare the surface and confirm surface moisture is less than 25%. Remove dirt, grime, efflorescence, lime run, construction debris, form oils and release agents, chalked materials, loose and peeling paint, mold, mildew, etc. All cracks should be pointed or caulked.
    2) Step Two: Perform a test application to confirm fit and finish.
    3) Step Three: Apply the product according to It’s TDS.
    4) Step Four: Let cure.
    5) Step Five: Perform post application test to assure results are achieved.

    Benefits of Concentrates and How to Mix

    The benefits of specifying Concentrates:

    • Reduces carbon footprint
    • Reduces job site and landfill waste
    • Reduces worker and supply chain fatigue
    1. Refer to the description on the packaging for dilution ratios.
    2. Pour contents of concentrate into an empty container. The container size should be the size of the finished amount of product.
    3. Fill the container with clean water – we recommend distilled water for best results.
    4. Mix lightly with a stir stick.

    Specification and Ordering Options


    Substrate Uses and Anticipated Coverage Rates

    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) 200-225 1
    CMU (Split Face) 180-200 1
    CMU (Scored/Fluted) 150-180 1
    CMU (Lightweight) 165-180 1
    Clay Brick 250-300 1
    Stucco 225-275 1
    Dense Masonry Surfaces 275-300 1
    Clay Block 175-200 1
    EIFS 150-180 1
    Concrete 250-300 1
    Concrete Curing Aid** 300-400 1

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

    **See TDS for details.

    Testing Data and Product Characteristics

    Testing Data

    ASTM C666 2200 Cycles – No effect
    ASTM C672 100 Cycles No Mass Loss, No Scaling
    ASTM D2243 Do Not Freeze
    ASTM G154 2,500 Hours No Loss in Repellency
    ASTM C672/M 100 Cycles Treated Concrete, No Scaling
    ASTM E-514 98.7% Leak Red Water, Wind Driven Rain
    SS-W-110C, ASTM C140 Water Pen Fed Spec, SS-W-110C, 75% Min Req, 97.2% Leak Red Chloride Ion Intr
    Salt Pounding NCHRP No. 244 Series IV – 95%, Red No. 244 Series II – 87% Red
    Chloride Ion Absorption No. 244 Series II – 87%
    Water Abs CMU ASTM C140-75 98.2% Effective
    Water Vapor Trans ASTM D-1653-71 100% Vapor Permeable
    Water Repellency ASTM C67-87 98.2% Effective
    Weathering ASTM G-53 3,500 Hours- No Change
    Surface Burning ASTM E84 Flame Spread 0, Smoke Development 0
    ASTM C 309 Pass
    ASTM C1315 Type I, Class B

    Product Characteristics

    Material Type Acrylic Copolymer Emulsion
    Active Content 100%
    Volume Solids 44%
    Color of Material Opal White
    Odor Slight Odor
    V.O.C. 0 g/L V.O.C. Compliant in North America
    Flash Point Non-Flammable
    pH Value 8.0-9.0
    Viscosity 9.6 Seconds No. 4 Ford Cup
    Weight Approximately 8.6 lbs./Gal.
    Surface Dry/Recoat/Usable Approximately 1 Hour
    Coalescence Cure Time 5 to 7 days

    Approvals, Qualifications and Associations

    Call 1-888-765-7070 Option 2 for additional assistance.

    LAUSD – OESH Approved
    LEED Points Up to 3 Points
    LEED (New Construction) Available
    LEED (New Schools/CHPS) Available
    CARB Compliant
    SCAQMD Compliant
    All Other States and Canada Compliant
    FDA Meets Requirements
    USGBC Member
    APTA Member
    HPD Various Products Approved
    American Institute of Architecture Two Approved CE courses

    We’re Here to Help!

    Call 888-765-7070