How to determine if a fiberglass hull is damaged?

Boating enthusiasts agree that a fiberglass hull is by far the most popular material for building boats, thanks to its durability, resilience, and ease of maintenance. However, just like any other material, fiberglass can sustain damage from various factors, such as impact, weather, and age. But how do you determine if a fiberglass hull is damaged? Here’s what you need to know.

1. Inspect for Cracks and Fractures

The most apparent signs of hull damage are cracks and fractures on the surface. Look for spiderweb-like cracks, which indicate that the hull has hit something hard. Hairline fractures may look benign, but they can grow over time and create bigger issues. Start by surveying the hull’s exterior, and if you spot any signs of cracks or fractures, use a flashlight to examine the interior of the hull.

2. Study the Hull’s Shape

Another indicator of hull damage is a change in the boat’s shape. Using a straight edge ruler, place it against the hull, and compare it to the manufacturer’s specs. Any noticeable deviations from the straight edge indicate that the hull has sustained some form of damage. Check from different angles to make sure there are no discrepancies.

3. Inspect for Blisters

Blisters occur when water gets trapped between the gel coat and fiberglass layers and causes them to separate. Blisters may seem harmless, but they can cause extensive damage and weaken the hull’s integrity. Inspect the hull carefully, paying attention to any small bumps or indentations. Use a small needle or awl to puncture any bubbles and check if water comes out.

4. Look for Soft Spots

Soft spots or delamination occur when the different layers within the hull separate from each other. They may feel soft or spongy to the touch and can lead to leaks or more significant damage if not fixed in time. Walk on the boat’s surface, and if you feel any soft spots, mark them for future inspection.

5. Check for Moisture and Water Absorption

Fiberglass is prone to water absorption, and it can have severe consequences on the hull’s overall strength. Use a moisture meter to detect any moisture within the hull’s layers, which will indicate delamination or water intrusion.

Determining if a fiberglass hull is damaged requires a keen eye and sometimes specialized tools. If you notice any of the above signs, it’s best to seek the advice of a professional to evaluate the extent of the damage and provide remedial action. Remember, it’s better to catch and repair hull damage early before it turns into a costly, irreparable problem.

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