How to Restore a Fiberglass Boat Finish

When a fiberglass boat isn’t cleaned and waxed regularly, it loses its shine and takes on a dull, chalky appearance. 

Fiberglass boat finish restoration

This is caused by the gelcoat oxidizing and suffering water damage. It doesn’t look very appealing, but the good news is that restoring the shine to a fiberglass boat and returning it to a dazzling finish is pretty straightforward.

Why Fiberglass Boats Lose Their Shine

Fiberglass boats have a protective outer layer called gelcoat.

Fiberglass hull gelcoat finish

The gelcoat plays no structural role in the construction of a boat, but it does form a protective barrier between the fiberglass and the elements, in particular UV rays and water. It also provides the glossy shine we love, and gelcoat is often pigmented to add rich color to a boat. 

Over time, exposure to harsh UV rays and moisture causes the gelcoat to oxidize, a chemical reaction that breaks down the surface. Oxidation leaves gelcoat feeling rough to the touch, and gives it that slightly opaque, chalky look. 

Fiberglass boat finish faded gelcoat

When gelcoat oxidizes, it enables water to penetrate the surface. The water works into the compromised surface to form tiny pits, and eventually blisters and bubbles. The sooner you restore your fiberglass boat’s finish, the better, because oxidation and water damage get worse, and make the restoration process much more difficult. Gelcoat repair products are available to fix damaged fiberglass surfaces, but we'll focus here on restoration, not repair.

Restoring a Boat’s Finish

To restore shine to a fiberglass boat, it’s necessary to remove the oxidized portion of the gelcoat, and return the outer surface to the glassy reflective finish it once had. 

How to restore fiberglass boat finish

It’s necessary to polish, or compound first and then polish the boat to restore the finish. Polish is a mild abrasive that gently removes the very topmost surface of the gelcoat that has oxidized. The polish removes the chalky discoloration, and leaves the surface of the gelcoat mirror-flat once again

Fiberglass boat finish polishing

Compound is a slightly more abrasive version of polish, and is used on gelcoat that has been neglected for a longer period and is heavily oxidized and pitted. After oxidized gelcoat is compounded, it’s necessary to polish it to get that smooth glassy finish.

Protecting a Boat’s Finish

The next step after compounding and/or polishing off the oxidation is to wax the boat. 

Fiberglass boat finish polish and wax

Wax provides a protective layer over the gelcoat that helps prevent further oxidation. If the boat isn’t waxed after it’s polished, the gelcoat will quickly oxidize again, and you’ll be forced to compound and/or polish it once more. Applying two or more coats of wax offers maximum protection to the gelcoat. 

Preventing Further Oxidation

Compounding and polishing a boat is time consuming and exhausting work.

Fiberglass hull boat finish wax restoration

However, if you wax your boat regularly (at least twice a year or more if it’s exposed to extreme conditions), you may never need to polish or compound it again. Regular waxing preserves that reflective shine, which helps maximize your boat’s resale value should you ever decide to part with it. 

There are plenty of fiberglass boat restoration products available such as wax-sealer, boat wax and cleaner wax. As with most products, you get what you pay for, so keep in mind that cheap products rarely produce the same results as premium products.

Fiberglass boat finish

Whenever you’re ready to restore the fiberglass finish to your boat, find all the boat maintenance and cleaning supplies you need to get the job done here at!




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