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  • Micro-Seal® HD Silane / Siloxane Water Repellent

    • A high solids invisible water repellent
    • Protects against stains caused by oil, gas, and brake fluids
    • Penetrating formula for horizontal & vertical porous surfaces
    • Dries with a natural finish that will not yellow
    • Protects against water intrusion, efflorescence, lime, spalling, freeze/thaw damage, stains, mold, mildew, and UV damage
    • Zero VOC, eco-friendly, water-based, & made in USA
    MICRO-SEAL® HD Up to 20 Yr Material Warranty

    Only need a 10 Year Material Warranty or less?
    See Micro-Seal® Water Repellent

    Product Overview  |  Technical Data
    Coverage Rates  |  Application Guidelines

    Item #: CR-0401
    1 Gallon
    Ready to Use


    Item #: CR-0405
    5 Gallons
    Ready to Use


    Item #: CR-2405
    32 Oz
    Super Concentrate
    Makes 5 Gallons


    Item #: CR-2401
    1 Gallon Concentrate
    Makes 10 Gallons


    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.

    View Technical Documents


    • 100% Deep penetrating Silane Siloxane waterproof protection coating with up to a 20 yr warranty
    • Extensive ASTM tested for superior resistance to water, salt and wind driven rain
    • Stain resistant to oil, gas, dirt and grime for outstanding protection
    • Will not alter surface appearance – leaves no surface film, no sheen and will not yellow
    • Excellent Mold and mildew inhibitor – stops growth dead in its tracks
    • Save money with one coat application & quick 1 hour recoat window for a 2nd coat
    • Apply in cold weather down to 40°F (4.4°C) and newly poured concrete within 48 hours

    Coverage Rates (Theoretical)


    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

    *Some surfaces are more porous than others and may require additional coats. Please refer to the Technical Data Sheet below for full application guidelines. If you have further questions, please give us a call at (888) 765-7070 or email

    How to Use

    1) Prepare Surface

    To apply, surface moisture content must be less than 25% as measured with an electronic moisture meter. Surfaces must be free of 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.

    Do not apply if rain, snow, or temperatures below 40°F are expected within 48 hours. Do not apply if relative humidity is greater than 80%.

    2) Dilute (If Concentrate)

    Mix with fresh water — See Technical Data Sheet (TDS) below for ratio

    3) Apply Micro-Seal® HD

    Apply Micro-Seal® HD with low-pressure airless spray equipment. Use a spray tip size of .035 to .051. Hold spray head 8 to 12 inches from the surface. Multiple coats may be applied, whiting/yellowing will not occur. Micro-Seal® HD dries in 1 hour and fully cures in 5 to 7 days.


    Technical Documents



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