Supporting photo - Siloxa-Tek 8505

No oil, no odor, no nonsense

Defend your concrete from water ingress, deicing salts and oil with confidence. This water-based formula makes oil and grease stains easier to clean, and resists freeze-thaw damage, mold and mildew. It's the perfect sidekick for even the most mobile voyager.

Get Oil & Grease off the street

Use 8505 on a variety of concrete, brick and masonry applications where oil, grease, mold and mildew are the primary concern. It's easily applied with a low-pressure sprayer, roller or brush, and provides long-lasting ward to help you clean up the scum.

  • Concrete / Brick / Masonry
  • Concrete Blocks / Cinderblocks
  • Pavers / Exposed Aggregate
  • Slate / Stone / Stucco
  • Driveways / Sidewalks
  • Patios / Pool Decks
  • Garages
Supporting photo - Siloxa-Tek 8505

Dries Invisible

Imbue your concrete with the power of resistance while preserving the original appearance. Available ready to use or concentrated (5x). Use stand-alone or pair with a densifiying primer to increase performance and abrasion resistance.

Repels Water

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Resists Salt

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Resists Oil

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Available Concentrated

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Which is Best for You?

  • 8500 Concrete Sealer Bottle Image
    Siloxa-Tek 8500
    Protects Against
    Water & Salt
    In Stock
    Concentrated & Ready-to-Use
  • /product/siloxa-tek-8505 Concrete Sealer Bottle Image
    Siloxa-Tek 8505
    Protects Against
    Water, Oil & Salt
    In Stock
    Concentrated & Ready-to-Use
    Current Product
  • 8510 Concrete Sealer Bottle Image
    Siloxa-Tek 8510
    Protects Against
    Water, Oil & Salt
    In Stock

Product Details

    • Excellent waterproofing - Penetrates deep within the concrete chemically reacting within the pores and capillaries creating a long-lasting hydrophobic surface that beads water
    • Resists staining from oil and grease - Oleophobic fluorocarbon makes oil and grease easier to clean from treated surfaces decreasing maintenance requirements
    • 100% breathable - Non-film forming. Allows moisture within the concrete to escape without adverse effects to the sealer. Does not trap moisture
    • Reduces moisture intrusion - Resists wind-driven rain, prevents freeze-thaw damage, spalling, pitting and cracking.
    • Resists atmospheric staining - Resists mold, mildew, lichen, efflorescence and dirt pick up
    • Improves durability - Prevents capillary uptake of water and the aggressive substances dissolved in it
    • Natural flat finish - Does not change surface appearance, UV stable will not breakdown with light exposure
    • Can be applied to cured, honed and polished concrete - Ideal for horizontal surfaces such as garage floors, compatible with silicate densifiers
    • Water based - Low VOC’s, environmentally friendly
  • Surface Preparation

    1. New “green” concrete must be properly cured. Concrete should obtain 80% of design strength, typically achieved within 14-28 days. 2. The concrete substrate must be structurally sound and clean of oil, grease, dirt, wax, curing compounds, efflorescence, paints, previous sealers, adhesives and other contaminants that might interfere with the penetration of the sealer. Power wash, acid etch or mechanically scarify as necessary to achieve the desired surface condition. Allow for proper dry time before application. The surface-zone moisture content of the concrete should not exceed 4% wt. Do not apply if standing water is visible.
    2. Surface and air temperatures must be at least 40°F during application. Surface and air temperatures should not exceed 95°F. Do not apply when temperatures are expected to fall below 32°F within 8 hours or when rain is expected within 12 hours following application. Keep material from freezing. If freezing conditions exist before application, let the substrate thaw before application. Do not apply during inclement weather or when inclement weather is expected within 12 hours.
    3. Crack, patching and expansion joint sealants can be applied before or after application; always test for compatibility and adhesion.
    4. Protect people, property, vehicles, window glass, roofing materials, plastic products, shrubbery, landscaping and all surfaces not set for treatment from overspray.

    Application - Ready to Use

    1. Always test a small area before application to ensure desired performance, aesthetics, coverage rates and to verify application technique. Let test area dry thoroughly, 5-7 days, before inspection.
    2. Stir material throughly before and during application. Do not dilute or alter material for purposes other than specified.
    3. Two wet-on-wet coats are needed to ensure complete coverage. Apply with a roller, brush or low-pressure non-atomizing sprayer. Apply to saturation and let the first coat penetrate for 5-10 minutes then reapply a second coat in the same saturating manner. Less material will be needed for the second coat. Roll or broom out any puddles until the sealer penetrates the substrate. If it starts to rain, stop treatment and cover the impregnated areas.

    Dry Time

    Typical drying time is 4-6 hours at 70°F and 50% relative humidity. Cooler temperatures or higher relative humidity can extend the drying time. Treated surfaces will be ready for pedestrian and vehicle traffic within 24 hours. Water repellency will continue to develop within 7 days of application.

    Clean Up

    Clean equipment, tools and surfaces with hot soapy water. Unused or old material may be disposed of in a waste disposal site in accordance with local, state and federal laws.


    Avoid contact with skin, eyes and clothing, do not take internally. Use appropriate safety equipment during application and handling. Please refer to the safety data sheet (SDS) for additional precautionary instructions before use.

    Best Performance

    • Proper application is the responsibility of the user.
    • Will not inhibit water penetration through unsound or cracked surfaces with defective flashing, caulking or structural waterproofing.
    • Spills should not be allowed to sit for extended periods of time, clean all spills in a timely manner.
    • Make sure the most current versions of product data sheets and safety data sheets are being used.


    1 coat: 150 - 400 square feet per gallon. 2 coats: 75 - 200 square feet per gallon. Variations in texture and porosity of substrate will affect the coverage and performance of the product.

  • What does wet-on-wet mean? Wet-on-wet means that the second coat is applied while the first coat is still wet. Two coats of the Siloxa-Tek 8505 are required wet-on-wet. The second coat is applied immediately after the first coat while the first coat is still wet, since the Siloxa-Tek 8505 is a hydrophobic product it will try to repel the second coat if the second coat is applied after the first coat has dried.

    Can I walk on the first coat to apply the second coat? Yes, you can walk on the first coat to apply the second coat. Since the Siloxa-Tek 8505 is a penetrating sealer it will dry invisible and will not show footprints.

    Can I paint after sealing? In order to continue repelling oils and staining we do not recommend painting over the Siloxa-Tek 8505

    Does the concrete need to be dry before sealing? Yes, the concrete needs to be as dry as possible before sealing. We recommend the moisture content of the concrete be less than 4%wt. It is recommended to wait at least 24-48 hours after rain and pressure washing before sealing.

    How many gallons do I need to treat 250 square feet? The ready to use gallon will cover up to 250 square feet per gallon per coat. You will need 2 gallons of Siloxa-Tek 8505 ready to use to treat 250 square feet.

    What can I use to apply this product? The Siloxa-Tek 8505 can be applied with a garden variety pump sprayer, 3/8" nap paint roller or a brush.

    How do I clean out the sprayer after sealing? Since the Siloxa-Tek 8505 is a water based product you can use regular soap and water to clean out the sprayer and other application tools.

    How do I get oil stains out of my concrete? We recommend a highly concentrated, oil busting dish soap, such as Dawn. Squirt it over the stain and spread it around to cover the entire affected area. Let it sit for about an hour, then mop up the dish soap and oil with a paper towel.

    The Siloxa-Tek 8505 dried tacky and sticky, what happened and how do I fix it? If over applied or applied past the point of the concrete's absorption the excess sealer material will dry on the surface leaving the concrete feeling tacky/sticky. In order to remediate this issue use a mixture of ammonia and water (typically 4 oz of ammonia : 1 gallon water ratio) and spray it on the concrete, wipe or broom the surface working in the mixture on the tacky/sticky areas.

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