Fiberglass Repair 101: What Boat Owners Should Know

Fiberglass boats are strong, light, and easy to maintain—but damage happens. Understanding the difference between cosmetic and structural issues helps you decide what can wait and what needs immediate attention.

How fiberglass hulls are built

Most boats use layers of glass fabric saturated with resin over a core material. Structural areas might include stitched biaxial cloth and higher-density cores, while topsides often use lighter laminates. The outer gelcoat provides UV protection and shine.

Cosmetic vs. structural damage

• Cosmetic: scratches, small chips, chalking gelcoat.
• Structural: soft decks, cracks radiating from fittings, collision impacts, water intrusion into core.

Repair steps at a glance

1. Assess and map the damage (moisture meter, tapping).
2. Grind a scarf bevel beyond the crack line.
3. Replace wet core if present; bond new core.
4. Lay up glass plies from small to large to rebuild thickness.
5. Fair the surface and recoat with gelcoat or paint.

When to call a professional

If you suspect core damage, keel strikes, or anything near through-hulls and engines, get a qualified shop involved. Correct structural repairs restore original strength and alignment—and protect resale value.

Tip: Photograph each stage and keep receipts. Documentation helps with surveys and insurance claims.

Need help? Our ABYC-certified team can assess damage remotely and provide a written estimate within 48 hours.