[PaulK]

Until you hit something and put a hole or crack in the fiberglass and water gets in. Perhaps without you realizing it.  Then the ballast of steel punchings starts to rust.  If you don’t catch it in time the expanding rust can blow the keel open and the ballast will all fall out. Freezing water inside the keel will do this as well. A few builders do make boats with encapsulated keels. (e.g. Island Packet) and make sure that information is included in their sales literature. Island Packet uses lead, so you don’t have to worry about rust –  only freezing. Brokers should be aware of any encapsulated keels in the boats they have listed and can tell customers when asked. Or the broker can be told that the potential buyer is only interested in encapsulated-keel boats, and let the broker do the research.