Hard or contact leaching antifouling paint dries to a hard but porous film that is packed with biocide. The biocide begins to leach out on contact with water to prevent fouling growth. This leaching is chemically designed to release biocide while the boat is in the water. Out of the water the paint film will oxidize and slow the release of the biocides to the point where there may not be enough biocide coming out of the paint film to maintain fouling protection. One of the main benefits of this type of antifouling is its resistance to abrasion and rubbing. This makes it ideal for fast powerboats, racing sailboats or boats where the owners have the bottoms scrubbed regularly.

Hard antifoulings from International^® include Interspeed Ultra, Navigator^® and VC^® Offshore

• Initial maximum time before launch – Follow label instructions
• Boats that have been painted and are past the maximum time before launch on the label but no more than 12 months past their launch date – Scuff sand with 220-grit sandpaper or a maroon Scotch-Brite pad prior to launch.
• Boats painted more than 12 months prior to being launched – Sand with 80 - 100-grit sandpaper and recoat prior to launch
• Boats that have been launched but are in the water for less than 24 hours – Lightly pressure wash to remove surface contamination (salt and dirt etc.). Follow label instructions for maximum launch time from date of painting.
• Boats that have been in the water for more than 24 hours but less than 30 days – Pressure wash immediately after hauling. No additional work is needed if the boat is relaunched with 72 hours. IF the boat will be out of the water for more than 72 hours will need to be sanded with 220-grit sandpaper immediately prior to relaunching.
• Boats that have been in the water for more than 30 days – Pressure wash when hauled, sand with 80 or 100-grit sandpaper and recoat. Recoating is necessary even if the boat will be out of the water for less than 72 hours.