Pressure treated wood is created using chemicals and other materials that need to properly cure prior to applying a waterproofing sealer or 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® NANO GUARDTM, if the product is applied too soon, the chemicals in the wood can prevent penetration, which will inhibit our product’s ability to protect the wood from water damage. The best way to determine if pressure treated wood has cured, and is ready for SEAL-ONCE products to be applied, is to pour 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 NANO GUARD, NANO GUARD PLUS POLY or ACRYLIC POLY to be applied.