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  • Micro-Seal® HD Silane / Siloxane Water Repellent

    Penetrating Silane/Siloxane Technology
    Ensures your project is protected from water intrusion, efflorescence, lime, spalling, freeze/thaw damage, stains, mold, mildew, and UV damage.

    Natural Finish
    Preserves the look of the building with a natural permeable finish and will not yellow.

    Safe to use
    Can be applied anywhere in North America because it contains Zero VOC, no carcinogens, no odor and can be applied on exterior surfaces and interior OEM environments.

    Easy to apply
    With a flood coat. Warranty up to 20 years.

    Micro-Seal® HD Silane / Siloxane Water Repellent

    Protect, restore and extend the life of your project with Micro-Seal® HD Clear Finish Silane / Siloxane Waterproof Coating. Made from the best water repellent chemicals in the construction market, Micro-Seal® HD is formulated by blending silanes and siloxanes that have long been trusted by architects, engineers and building owners around the globe. Micro-Seal® HD creates a hydrophobic barrier that is not affected by weathering, salt, dirt, freezing temperatures, UV light and wind-driven rain, among many other damaging elements.

    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

    Substrate porosity varies due to type of substrate and/or the age of the surface and its exposure to weathering. As a result, coverage rates may also vary. In addition, in certain applications, two coats may be required. Please contact us for coverage estimates. Best practices are to first perform a test application on the substrate, followed by a rilem tube test to ensure adequate coverage/absorption.

    Refer to the product TDS for Surface Preparation and Application Methods.

    Need help? Call 1-888-765-7070 Option 2.

    Substrate Sq Ft / Gallon # of Coats*
    Wood 160-210 1
    Concrete and Masonry Block 50-80 1
    Lightweight Block 40-55 1
    Adobe Block/Natural Stone 70-90 1
    Clay Brick 60-70 1
    Stucco 110-160 1
    Concrete (vertical & horizontal) 135-160 1
    Concrete Curing 310-410 1
    EFIS 90-130 1

    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 Pen Fed Spec
    SS-W-110C, ASTM C140 75% Min Required, 96.8% Leak Reduction
    ASTM D-1653 98.6% Effective
    ASTM C67 100% Vapor Permeable
    ASTM G 98.6% Effective
    ASTM E84 3,500 Hours- No Change
    NCHRP No. 244 95% Reduction, Series IV Salt Pounding
    87% Reduction, Series II Salt Pounding
    87% Reduction, Series II Chloride Ion Absorption

    Product Characteristics

    Silane/Siloxane Active Content 100%
    Reactive Solids 40%
    Volume Solids 4%
    Color of Material Milky White
    Odor Slight Odor
    V.O.C. 0 g/L V.O.C. Compliant in North America
    Flash Point Non-Flammable
    pH Value 6
    Viscosity 9.6 Seconds No. 4 Ford Cup
    Weight Approximately 8.7 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