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Can VS721 be applied over Interlux VC Offshore


Jay Hoppenstein has submitted the following:

My J105 has VC Offshore applied to its bottom. This is a “hard” paint applied over a barrier coat. The boat is kept in fresh lake water in Dallas, Texas. Can VS721 be applied over the VC Offshore after the bottom has been power washed, cleaned with one of your Scrub products and allowed to dry?

If so, does it harm the VS721 to use a Hydrohoist lift (to be used in the near future)to keep the hull out of the water?


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We do not recommend that you apply VS721 over antifouling paints for several reasons:

1) VS721 is designed to cross link or bond securely to the substrate for durability and long life. If you apply it over paint, it may or may not bond to the paint and if it does, will only be as durable as the paint. If the paint is antifouling and sloughs or releases its surface or biocides into the water, it will also release the VS721 from the surface.

2) Antifouling paints are designed to poison marine life in the general vicinity of your boat. VS721 is non toxic and will seal the surface and prevent the antifouling from killing the marine life.

3) VS721 is very slick and works best on a smooth surface. Most antifouling paints tend to be somewhat rough. Even though they are sanded smooth they roughen up as they wear away.

4) antifouling paints are not the best surface for VS721 to attach to.VS721 is ideally suited to fiberglass or aluminum but can also be used over hard paints like poly urethanes or enamels that are sometimes used on boat hulls.

5) VS721 does not contain biocides and is a green product. Antifouling paints are not. They are not compatible.

Some boat owners have tried VS721 over antifouling paints such as VC17, be we have not had any feedback so we do not know how successful they were. Until we have some positive feedback, we can only recommend that you strip off the antifouling paint. A lot of boat owners would prefer to rid their boats of antifouling paint but put it off because they don’t want to deal with the hassle. Our R&D department has been working on a chemical paint removal system that works and they feel confident that they will have one soon.

VS721 can be exposed to air and water repeatedly without affecting its performance or durability. It’s very durable so that it will withstand scuffing that may occur from hoisting or trailering.

Thank you for your question,

Captain Aurora
Richard Kittar

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