The demand for more environmentally friendly and long-lasting products is pushing for innovation in the paint industry – benefiting boat owners and the ocean. After successful use over decades on thousands of commercial ships, foul release coatings are now taking the leisure boat industry by leaps and bounds. We’ll show you what to expect.
Foul release coating VS self-polishing antifouling
Self-polishing antifouling is the most sold antifouling paint in Norway. This type of antifouling ensures an even renewal of the paint film that releases biocides (usually copper and zinc) to prevent fouling from adhering to the hull. The self-polishing effect depends on the speed and activity of the boat. At the end of the season, you have certainly noticed that the top speed decreases and the fuel consumption increases. This is because the effect (amount of biocides) of self-polishing antifouling is greatest when the coating is new and its effect weakens over time, which in turn leads to fouling on the hull.
- The advantage: it works well when the coating is new and the toxins are fresh.
- The challenge: the effect is short-lived and you should apply a new layer every year. As a boat owner, this practice requires a lot of time and money spent on annual maintenance. At the same time you expose yourself to health-damaging maintenance both when applying and removing old layers of paint. For the environment, current practice with well documented release of heavy metals and plastic polymers has an adverse effect on marine life.
Foul release coatings
Foul release coatings have long been used in the shipping industry, but only recently have paint manufacturers started offering the technology to the leisure boat market. Silicone-based foul release coating is a non-toxic alternative to traditional self-polishing antifouling paint, where the speed of the boat produces a hydrodynamic shear that is needed for the loosely attached fouling to fall off. Fouling attaches to any surface that does not have poison in it, but on foul release coatings the fouling falls off easily during speed or by movements that simulate speed, e.g. by hand or water jet.
- The advantage: Foul release coating has a duration of several years, which eliminated the need for annual application. The coating is easy to wash and keep clean, without losing its properties. It is non-toxic and therefore does not affect the organisms in the sea. Reduced need for maintenance means that you, as a boat owner, avoid exposing yourself to health-damaging maintenance in both spring and autumn. (more than absolutely necessary)
- The challenge: Silicone-based foul release coating is soft, and requires that you take this into account when the boat is lifted in straps or hauled onto a trailer. A tip is to place a foam pad between the slings and the boat, but also on the boat stands on which the boat rests. If you have the boat on a trailer, hard plastic wheels should be covered in a soft rubber tape. The application process is a little more complex and time consuming than it is for traditional antifouling. Silicone coatings lasts longer when kept in the water, which suggests that off-shore winter storage is preferred.