How to Refinish the Hull of a Marine Boat

Wash the surface of the hull with a pressure washer.

Remove the old paint from the hull. If you have a very small boat, you can do this by hand using sandpaper, but more likely you'll need a pressure blaster. Be careful not to concentrate the pressure blaster on one spot for too long or you'll damage the hull.

Mix your epoxy of choice with resin hardener according to the ratio specified on the epoxy bottle. Mix them in a separate container using a paint stirrer, tongue depressor or other stick. The hardener helps the epoxy stick to the hull. The epoxy itself adds a layer of protective finish to the hull.

Apply one coat of the epoxy mixture with a paint brush or roller and let dry. Make sure to cover the whole hull.

Apply four to six layers of gel coat to the hull using a brush or sprayer. Each coat should be about .01 inch thick. Wait a couple hours for each coat to dry before applying the next coat. Also wait for the final coat to dry before proceeding to the next step.

Paint the hull of the boat using anti-fouling paint, which keeps contaminants and marine life from sticking to or growing on the hull. Use a brush or roller; a dropcloth is also advisable to avoid staining the area under the boat with paint. Apply two full coats. Most anti-fouling paints are copper-based, which can be environmentally harmful, but non-toxic and low-toxic anti-fouling paints are also available.