Here is an example of one of the worst cases of osmosis we have seen in a while.
What is osmosis?
The outer layer of your boat composition (gel coat) is not completely waterproof. Over the years, tiny amounts of water find their way through its ever-so-slightly permeable surface. This can then react with uncured chemicals in the glass fibre mat beneath, causing a by-product of pressure. This builds up to cause the blisters to appear.
Don’t panic as there are ways to fix it.
