Fiberglass damage happens. Some repairs are simple enough for any boat owner. Others require professional expertise. Here's how to assess damage and decide when to DIY.
Understanding Fiberglass Construction
- Gelcoat: Shiny outer layer—cosmetic and UV protection
- Fiberglass laminate: Layers of cloth and resin for strength
- Core (if present): Wood, foam, or honeycomb for stiffness
Types of Damage
Gelcoat Scratches — DIY: Easy
Surface scratches. Fix with rubbing compound, polish, and wax.
Gelcoat Chips — DIY: Moderate
Deeper damage not reaching fiberglass. Use gelcoat repair kit with color matching.
Spider Cracks — DIY: Moderate-Difficult
Web-like cracks from impact or flexing. Grind out, fill with gelcoat, sand and polish.
⚠️ Important
Spider cracks can indicate structural stress. If they're around hardware or high-stress areas, have a professional assess for structural damage.
Fiberglass Cracks/Holes — DIY: Difficult
Damage penetrating into laminate. Requires grinding, new fiberglass layup, fairing, and gelcoat.
Core Damage — Professional Recommended
Water in deck or hull core. Complex repair with serious consequences if done wrong.
Osmotic Blisters — Professional Recommended
Blisters in hull bottom. Widespread blistering often requires peeling and barrier coating entire hull.
When to Call a Professional
- Structural damage
- Below-waterline repairs
- Hull core damage
- Large areas
- If you're unsure
Find hull and fiberglass specialists in South Florida through Boatwork.
