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NANO+POLY Premium Wood Sealer

Long-lasting, Eco-Friendly Wood Protector & Stain

4.69 out of 5based on 13 customer ratings
13 customer reviews


  • Decks & Fences
  • Wood Siding
  • Log Homes
  • Planters & Railings
  • Exposed Beams
  • Outdoor Furniture
  • Play Structures
  • Cedar Shingles
  • Docks & Piers
  • Pergolas


  • Water-based, Ultra-Low VOC
  • Eco-friendly, Non-toxic, No Odor
  • Won't harm people, pets or plants
  • Penetrates below the surface
  • Creates flexible, breathable barrier
  • Prevents mold, mildew & wood rot
  • Stabilizes wood from warping
  • UV barrier protects from sun rays
  • Extends natural life of wood
  • Easy soap & water clean-up

SEAL-ONCE® NANO+POLYTM Premium Wood Sealer combines our proprietary nanotechnology formula with the strength of polyurethane to provide 360° of protection. The NANO creates a durable finish that allows wood to expand & contract, while the POLY adds surface protection against wear & tear in high traffic areas.

Unlike many sealers that only form a top-coat, NANO+POLYTM penetrates below the surface to form a long-lasting, water-resistant shield around the wood fibers at the cellular level.  This penetrating protection from water intrusion prevents wood rot, decay, mold & mildew.  It also stabilizes wood, eliminating warping & cupping.   It is a great investment to preserve old or new wood & extend its natural life for years.

NANO+POLYTM is UV stable, with UV blockers that protect from sun light to help prevent the natural color of the wood from fading.  When used as a wood stain, the tinted formula provides added UV protection.  NANO+POLYTM has no toxic chemicals like many oil & solvent based sealers,  so it can be applied around your home, landscaping, vegetation or over water safely.  Warranted to prevent long-standing water accumulation for up to 10 years on vertical & 6 years on horizontal surfaces.

Product Details

  • All surfaces should be cleaned before sealing for best penetration and performance.
  • Remove all old coatings, dust, debris and loose material. Remove oil, grease, algae, grime, mill glaze and mold and mildew stains with appropriate cleaners. Recommend SEAL-ONCE All Wood Cleaner.
  • Test absorbency after cleaning by sprinkling water on surface. If the water does not readily penetrate the surface, stripping will be necessary to remove old coatings.
  • Do not use if air or surface temperature is below 50°F/10°C or above 95°F/35°C.
  • Do not apply in rain or when rain is imminent.
  • DO NOT THIN. Mix well. Stir contents or shake thoroughly prior to use.
  • Test a small area to ensure acceptable appearance and penetration.
  • Apply first coat with a synthetic brush; pump-up garden sprayer; air-assisted and/or airless sprayer. Use 15-17 tip and medium to coarse spray pattern. When spraying, always back brush for best results.
  • Second coat can be applied once first coat has penetrated but is still damp. Second coat must be applied within one hour of applying first coat.
  • For best results, apply in the shade and out of direct sunlight.
  • Apply to all surfaces. Apply SEAL ENDS ONCE® to wood ends.
  • Do not use with other waterproofing products.
  • Allow approximately 3-4 hours for surface to dry, depending on temperature and humidity, before subjecting to light foot traffic.
  • Allow 24-48 hours for full cure, depending on temperature and humidity.
  • When recoating, apply once previous coat has penetrated and surface is damp, not wet. Second coat must be applied within one hour of applying first coat.
  • Clean all application equipment with warm soapy water.
  • Disposal: soap and water cleanup; no special disposal procedure needed.
  • Store unused product above 32°F/0°C to protect from freezing.
  • Shelf life (unopened): 2 years
  • Surfaces that have been treated with SEAL-ONCE NANO + POLY Premium Wood Sealer can be cleaned using a mixture of 1-gallon warm water, 14 oz. bleach, and 1 oz. of Dawn® dish detergent. Apply this cleaning solution with a sprayer and allow to sit for 20 to 30 minutes on the wood surface before rinsing with water using a garden hose with a nozzle.
  • This cleaning solution can be used to remove airborne mold and mildew stains, dirt and grime from the wood surface. NANO + POLY will prevent and resist any water, mold and mildew penetration. Do not use oxidizers, corrosives, or strippers on surfaces that have been treated with NANO + POLY.
  • Surfaces can be recoated with NANO + POLY at any time. NANO + POLY may need to be reapplied for fading tint color, surface damage, in heavily worn or high traffic areas, or in places where the surface may have undergone noticeable changes.
  • Before reapplying NANO + POLY, clean the surface using the recommended cleaning solution above. Apply NANO + POLY according to package instructions. When reapplying in small areas, lightly overlap onto areas previously treated with NANO + POLY.

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