Osmotic blistering occurs when water penetrates the fiberglass gelcoat and creates fluid-filled bubbles beneath the surface. It is common in boats kept in the water long-term and far less common in Lake Havasu's dry-stored boats. To check, look along the waterline and hull bottom for raised bubbles or pockmarks. A marine surveyor uses a moisture meter to detect subsurface moisture before blistering becomes visible. Repair can range from $500 to several thousand dollars depending on severity.
What is osmotic blistering and how do I check for it?
