Order as many floor samples as you like and we'll ship all samples to you for free! You may then return them, within six months, and receive a refund for all returned samples. Please note: We do not reimburse for return shipping costs.
We recommend a sample before you order!
We provide fast, free shipping on samples.
Green Building Supply, Penetrating Concrete Sealer
Green Building Supply, Penetrating Concrete Sealer
Safe, permanent waterproofing sealer for concrete, masonry, stucco or brick
Cold Weather Alert:
This product may not perform properly if applied below the required temperature. Please check installation instructions on our website.
Because this is a water-based product, it may freeze during shipping. For that reason we will not ship over a weekend if temperatures dip below 32 degrees F.
If you want us to ship anyway, it will be at your own risk. Please call to arrange with a GBS eco-advisor. 800.405.0222
GBS Penetrating Sealer is a waterborne polyester polymer and polyurethane that works best on concrete, brick, stucco and masonry. It waterproofs and preserves with 3-5 coats, plus it comes with a 15-year waterproofing warranty. Unlike topical sealers that sit on the surface and rub off with wear and tear, GBS Penetrating Sealer protects from inside the material where it can't wear away. In other words, this sealer actually becomes part of the substrate.
This sealer penetrates two to four inches deep, filling molecular voids to completely solidify the entire structure. When it dries, it becomes part of the structure creating a solid matrix. This means there's no room left for water to infiltrate and leak through. In addition, the substrate becomes stronger and lasts longer.
Dry time for indoors is apx. five days; outdoors 2-4 days depending upon temp and humidity. Allow 48 hours before walking on. Avoid using it before rain.
GBS Penetrating Sealer is solvent-free, odorless, non-flammable, non-caustic, and almost no VOC (5.9 g/l). Use it on basement walls and floors, retaining walls, pool surrounds, brick veneer walls, chimneys, fireplaces, concrete or limestone pavers, driveways, sidewalks, patios, warehouse floors, and historical renovations.
Quality Control Test results: GBS Penetrating Concrete Sealer has passed 9 independently performed quality tests per the HRP specifications. These tests include:
ASTM 413 - “Water Absorption of Chemical Resistant Concrete/Masonry” .
ASTM C140 - “Masonry Absorption Test for Light Weight Block”. ASTM requires that water absorption cannot exceed 1% after 2 days of immersion.
ASTM 123D - “Penetration Test for Nuclear Power Plant, 8000 psi Concrete Pour”.
Blue Dye Test - “Blue Dye Absorption Test”.
ASTM 642-82 - “Masonry Absorption Test for Brick”.
ASTM C672 - “Scaling Resistance”.
AS 1012.21-1999 - "Water Absorption of Hardened Concrete".
NCHRP 244 – Cube Test – “Accelerated Weathering Test”.
NCHRP 244 – Southern Exposure – “Chloride Ion Penetration Test”.
NOTE 1: GBS Penetrating Sealer should NOT be used in areas constantly under water such as cisterns. Also, any areas that have been power troweled, especially in basements, need to be acid etched or mechanically ground before application in order to open the pores. This product should not be used on stamped concrete. NOTE2: Do not use this product in working fireplaces as it is not suited to that kind of heat (may bubble and melt). NOTE3: If you plan on applying ceramic or porcelain tile to the surface at some point in the future, do not use this product. It will seal the concrete so well that the thinset will not adhere to the surface—unless, of course, it is etched or ground. NOTE4: This product will only perform well if applied correctly. Be sure to read and follow the application instructions. For proper adhesion, the surface must be:
Free of any other sealers, coatings, stamped concrete release agents
Neutral pH — between seven and nine
Please see the application instructions for details on each of the above steps.
Whether you want to stop your basement walls or floors from leaking, or just want to prevent deterioration of your mortar in a brick wall, this is the right product for the job. It's a smart way to prevent problems before they arise. An inexpensive insurance policy.
Features & benefits
Permanent waterproofing — becomes part of your material; 15-year warranty against water intrusion
Superior durable finish — penetrates in; can't rub off; protects against freeze-thaw
Strengthens substrate — extends material life; reduces efflorescence and concrete dusting
Easy-to-use — sprays on; no mixing required; water cleanup; pH strips provided
Non-toxic — no formaldehyde, ammonia, crystalline silica, ethylene glycol, mildewcides, fungicides, exempt solvents or aromatic hydrocarbons commonly used in sealers
Alert: This product will only perform well if applied correctly. Be sure to read and follow the application instructions. Test first to see how it affects your specific application.
State Nexus Fee may apply A state nexus fee will be applied to this item if drop shipped to the following states: . We're sorry for the inconvenience. Click here to read more about the state nexus fee.
Coverage (1 Coat)
Recommended # of Coats
3-5 coats until saturated. 3-5 coats will cover an average of 200 SF/gallon (depends on porosity)
Apply next coat after previous coat has been absorbed. Wet on Wet. Do not let dry between coats.
24-48 hours (outdoors), indoors 5 days (dependant on heat, humidity, airflow)
Yes, BUT can only be frozen in container 6-8 times
Residential Finish Wear
Commercial Finish Wear
Forest Stewardship Council (FSC)
FSC Chain-of-Custody #
LEED® Regional Materials Zip Code
Country of Manufacture
Use With These Products
Number of Colors
Critical Radiant Flux
Face or Pile Weight
Pile Height (High)
Pile Height (Low)
Resistance to Insect Pests
Stitches Per Inch
Surface Texture, Construction, Style
Tufts per Sq. In.
Tufts / Sq In
Bundles per Pallet
Bundles per Square 6" Exposure
Bundles per Square 7" Exposure
Bundles per Square 7-1/2" Exposure
Bundles per Square 8" Exposure
Pounds per Bundle
Pounds per Pallet
Pounds per Roll
Pounds per Square
Pounds per Square 6" Exposure
Pounds per Square 7" Exposure
Pounds per Square 7-1/2" Exposure
Pounds per Square 8" Exposure
Lin Feet per Bundle
Lin Feet per Pallet
Rolls per Pallet
Squares per Roll
Tiles per bundle
Tiles per Lin Foot
brush, roller, sponge, spray is best
Application Temperature Range
Warmer than 55°F
Surface should be Clean, Dry, Neutral pH, and Absorbant.
Test BEFORE applying. Power-troweled surfaces may not absorb well and should be etched with our Micro-Etch.
Apply in good weather when air and surface temperature are above 45°F. and surface temperature is at least 5°F. above the Dew Point. For optimum application properties, materials should be between 70-90°F prior to application. 1. Use a low pressure sprayer (Hudson type) or any sprayer operated at no more than 20 psi. Spray on with low-pressure sprayer and back roll using a 3/8 inch nap roller any puddles into a dry area with a low nap paint roller. The goal is to saturate the surface. This may require 3-5 passes, one after the other, WET ON WET application.
Note: If the concrete was power troweled, GBS Penetrating Sealer may not absorb at all. Using our MicroEtch product will open the pores and allow for proper penetration.
One gallon of GBS Penetrating Sealer covers approximately 200 square feet depending upon porosity. 2. Ideally you will work with two people. One spraying and one using a 3/8 inch nap paint roller to spread out excess (do not allow excess puddles to dry as results could be slippery). Clean the roller or brush with soap and water. 3. Allow to dry thoroughly before traffic is allowed onto the floor; indoors approx 5 days, outdoors 24-48 hours depending upon temp, humidity, and air flow; avoid using before rain. 4. 6 to 7 days for completion of penetration/curing process. 5. If you are using GBS Penetrating Sealer before painting, allow-dry a minimum of three days prior to the application of paint. GBS Penetrating Sealer will waterproof the surface so well that non-moisture resistant paints (such as but not limited to latex) should NOT be used. Use only good quality moisture-resistant paint such as 100% acrylic or oil-based paint. We recommend AFM SafeCoat Concrete Floor Paint or ECOS Interior Floor Paint / ECOS Interior Anti-Slip Floor Paint. Note: GBS Penetrating Sealer will not harm glass, aluminum, metal, plants or aquatic life. If GBS Penetrating Sealer gets on glass, rinse off so it doesn't dry. Not recommended for painted stucco (unpainted is fine) and submerged areas in pools or ponds. Not for use in working fireplaces.
Surface or Product Preparation
Always test GBS Penetrating Sealer in a small inconspicuous location first. When in doubt, call us at 1-800-405-0222.
FOUR Surface Requirements BEFORE Applying:
4) Neutral pH - I - POROUS
Porous means it should be able to soak in easily. If there are sealers, paint or adhesives on the surface they will disallow absorption. If the surface has been power-troweled it will also make the surface so dense that water will not soak in easily.
How to Test? Place a few drops of water onto the surface and see if it beads up or soaks in. If it soaks in and darkens, then the surface is porous and GBS Penetrating Sealer will also soak in. Nothing need be done except to make sure it is clean, dry, and have a neutral pH. See #2 and #3 below.
If, however, it beads up and does not soak in for about an hour, then there is either something on the surface or it has been power-troweled.
If power troweled, use our GBS MicroEtch product to open the pores without toxic chemicals. Do NOT acid etch. Or you can grind with a surface grinder that can be rented from most rental stores.
NOTE: GBS Penetrating Sealer will not work over stamped concrete.
If there is latex paint, adhesives, or other acrylic sealers on the surface we recommend our GBS Industrial Strength Cleaner (If it is unknown what type of sealer was used, we recommend purchasing a test sample of the cleaner as some sealers cannot be chemically removed).
If efflorescence (white powder), rust stains, red clay stains appear on the surface, use a non-toxic acidic cleaner (Outdoor use only). - II - CLEAN
Clean means washed with a neutral pH detergent and then dried thoroughly. Ideally use a 3000 psi pressure washer. If you are indoors, this may be difficult so use a damp mop instead. If you have used a cleaner mentioned above or any other strong cleaner you should wash at least twice and rinse at least three times. Then dry well for several days. - III - DRY
After cleaning, use fans, heat, open windows or a shop vac to remove all water. If there is any water inside the concrete, it will prevent the sealer from soaking in. If it's humid, cold or damp, this could take longer to dry out. Be patient. Even if it appears dry on the surface, moisture may still be inside the concrete. Use a moisture meter to test or wait at least two days during warm weather or three days during cool weather.
NOTE: New concrete, even though appearing dry, is still very wet inside. Therefore, you should wait a minimum of 3-4 weeks until it has dried inside. This can be accelerated with heat, fans, and good ventilation. - IV - NEUTRAL pH
New concrete has a high pH. For GBS Penetrating Sealer to work properly, the concrete needs to be in the pH 7-9 range to work well. No higher, no lower.
We provide litmus paper so you can test in several areas. Be sure to use distilled water with the litmus test.
What to do if the pH is still high after testing? Concrete less than one year old is often still high in pH. If so, you can use our GBS pH Reducer. This will bring the pH down to acceptable levels with a few hours. Then it should be washed off as explained in #2 above. Note: If you need to open the pores due to power troweled surface then our GBS Micro Etch product is sufficient. You don't need both products. - OTHER LIMITATIONS -
Apply in good weather when air and surface temperature are above 45°F. and surface temperature is at least 5°F. above the Dew Point. For optimum application properties, materials should be between 70-90°F prior to application. Maintain unused material in closed containers in protected storage at 40-90°F out of direct sunlight. Not intended to be used submerged in water for an extended period of time. If the surface does NOT absorb water, then there is possibly another sealer applied to the surface and GBS Penetrating Sealer should not be applied. - IF PAINTING OVER AFTERWORD -
To paint over a GBS Penetrating Sealer treated area use only a good quality acrylic, oil-base, epoxy, or urethane paint. Do not use latex paint over a GBS Penetrating Sealer coated surface since latex paint makes a weak bond, especially in exterior applications. We recommend AFM SafeCoat Concrete Floor Paint or ECOS Interior Floor Paint / ECOS Interior Anti-Slip Floor Paint.
Appearance When Dry
No change to surface color or sheen.
Cleans Up With
Store in cool dry place out of sunlight
Recycling or Disposal
Dispose of excess product in accordance with all local state and federal regulations, Do not throw out container unless completely empty. Pour contents onto dry cardboard and let thoroughly dry outdoors. May also be absorbed with cat litter sand or other dry materials