What is fiberglass osmosis and how can I prevent it?
Fiberglass osmosis presents itself as a small round bulge on a fiberglass hull. This phenomenon is due to water diffusion through a permeable hull. Small air bubbles trapped within the fiberglass structure during construction are the starting point for osmosis. Osmosis has multiple causes; the production process, the quality of the materials used or a resin with low waterproof capacity. Blisters that have formed within the layers of fiberglass laminate are considered lesions of the hull and should be treated.
It’s possible to apply a preventive treatment in order to slow the appearance of this phenomenon. After hauling and securing your pleasure craft, the following steps are carried out:
- Stripping of the anti-fouling layer in order to expose the underlying layer of gel-coat;
- Surface preparation through sanding;
- Pressure washing with fresh water and specific detergents;
- Application of an epoxy primer anti-osmosis treatment;
- Application of an anti-fouling primer;
- Final application of three layers of anti-fouling.
This preventive treatment offers superior waterproofing to the fiberglass hull.