Common Questions

SEAL-ONCE products can be used on wood, concrete or masonry. This includes hardwood, softwood, pressure-treated wood, exotic wood, wood siding, log homes, cedar shakes and wood decking. Our products can also be applied to stucco, clay tiles, paver blocks, bricks, poured and stamped concrete, grout and mortar.

SEAL-ONCE NANO is a non-film forming, deep-penetrating, water based formula that creates a flexible, breathable barrier to protect wood against damage caused by water ingress. It is ideal for vertical surfaces and areas that will not be subjected to a high level of wear and tear.

SEAL-ONCE NANO+POLY combines our proprietary nanotechnology formula with the strength of polyurethane to provide 360° of protection for wood, concrete and masonry. It is ideal for high traffic applications such as decks and patios.

SEAL-ONCE NANO, MARINE, SEAL ENDS ONCE and Multi-Surface Concentrate are fully cured within 12-24 hours, depending on temperature and humidity. SEAL-ONCE NANO+POLY and EXOTIC are fully cured within 24-48 hours, depending on temperature and humidity.

We recommend waiting until it will not rain within the full cure time for the product you are applying. Please refer to the appropriate Technical Data Sheet for cure times.

SEAL-ONCE NANO deeply penetrates the wood surface by utilizing proprietary nanotechnology to create a flexible, breathable barrier that prevents water damage and decay and allows water vapor to escape. It is non-film forming and will not peel.

SEAL-ONCE wood sealers are compatible with our Semi-Transparent Wood Tints. These tints and stains are sold separately and are added in a 1:1 ratio; one tint bottle per one gallon of SEAL-ONCE. The colors can be added to SEAL-ONCE NANO, NANO+POLY, EXOTIC and MARINE. When using Multi-Surface Concentrate, color can be added for wood applications after the base product has been properly diluted.

The colors cannot be added to SEAL-ONCE POLY or SEAL ENDS ONCE.

Yes, SEAL-ONCE products are safe for both interior and exterior use.

Yes, SEAL-ONCE products are water based, do not contain any harmful chemicals or toxins and are ultra-low VOC. Our products can be safely applied and will not harm pets, plants, people and marine life. Additionally, our products do not require special personal protective equipment (PPE) and can easily be cleaned up using soap and water.

Product Application Questions

SEAL-ONCE must be applied to bare wood. If the surface has been previously coated with another stain or sealer, that product must be removed. Common practices for preparing your wood project include power washing, using a cleaner such as our All Wood Cleaner, sanding the surface or using a stripper to remove all previous stains and coatings   Ensure all surfaces have been properly cleaned by using the appropriate SEAL-ONCE cleaner (All Wood Cleaner or Concrete/Masonry Cleaner).  After cleaning, rinse the surface with water and allow to dry completely. Once the surface has been cleaned and the old coating has been removed, SEAL-ONCE products can be applied, according to the package instructions.

Yes, we recommend covering all surrounding materials and surfaces, as well as wiping down or removing all areas impacted by over-spray while still wet. While all SEAL-ONCE products are eco-friendly and will not harm the surrounding landscaping, it is advised that you cover any adjacent walls or materials that are not recommended for coating with SEAL-ONCE, especially if you are using one of our Semi-Transparent Tints.

No, you do not need special equipment. SEAL-ONCE products can be applied using a synthetic brush or stain pad. For faster application, a pump sprayer with a 0.015-0.017 tip can be used.  Additional application information is listed on our Technical Data Sheets, which can be found on our Data Sheets & Guides page.

The temperature range for applying SEAL-ONCE NANO, MARINE, SEAL ENDS ONCE and Multi-Surface Concentrate is 45°F (7.22°C) to 95°F (35°C). The temperature range for applying SEAL-ONCE NANO+POLY, EXOTIC and POLY is 50°F (10°C) to 95°F (35°C). These temperature ranges apply to both surface and air temperature for wood and concrete.

Product Application Questions > SEAL-ONCE NANO

No, tinted SEAL-ONCE NANO will not leave streaks when applied properly. When following our instructions for applying two (2) coats “wet on damp,” the second coat will blend evenly into the first.

The second coat of SEAL-ONCE NANO can be applied as soon as the first coat has penetrated but is still damp. The second coat must be applied within one hour of applying the first coat.

Product Application Questions > SEAL-ONCE NANO + POLY

The second coat of SEAL-ONCE NANO + POLY can be applied as soon as the first coat has penetrated but is still damp. The second coat must be applied within one hour of applying the first coat.

Seal-Once Semi-Transparent Tints

All of our tints and stains are semi-transparent and allow the natural color and grain of the wood to show through. The color charts on our website have been created using two coats of our tinted SEAL-ONCE products on red cedar. If you are coating a different material, you may see different results. Using more than two coats will also result in a darker, more saturated appearance. The color may also vary depending on which formula you are using as the colors may appear darker or more saturated in some formulas.

We offer 4oz pre-mixed bottles of all of our semi-transparent tints for testing on the material you are coating. Samples can be purchased in our webstore.

No, only the SEAL-ONCE® semi-transparent tints have been specially formulated for our products. Other colors or pigments may alter the effectiveness of our products.

Substrate-Specific Questions > Concrete

Yes, SEAL-ONCE NANO+POLY prevent efflorescence, which occurs when water penetrates the concrete and leaches out naturally-occurring salts, creating undesirable white stains on the concrete. Efflorescence must be removed prior to applying SEAL-ONCE, if it is already present on the surface.

Yes, SEAL-ONCE NANO+POLY can be applied to green concrete after nine days.

Substrate-Specific Questions > Wood

Pressure treated wood is created using chemicals and other materials that need to properly cure prior to applying a waterproofing sealer or other coating. If a sealer or coating is applied to pressure treated wood before it has cured, it can result in peeling, cracking, bubbling and other adhesion problems. In the case of SEAL-ONCE products, if the they are applied too soon, the chemicals in the wood will prevent penetration, which will inhibit the product’s ability to protect the wood. The best way to determine if pressure treated wood has cured, and is ready for SEAL-ONCE products to be applied, is to sprinkle water on the surface to see if it soaks in or pools. If the water soaks in, the wood has cured and is ready for SEAL-ONCE to be applied. If it pools or forms droplets, you need to wait longer before applying SEAL-ONCE.

SEAL-ONCE NANO, MARINE, EXOTIC and NANO+POLY can be applied to freshly cut wood because they create a breathable barrier that allows water vapor to escape as the wood ages.