# Solid hull



## Irv775 (Oct 28, 2018)

Does any know what Sailboats have solid fiberglass hulls? I fear an older boat with plywood wrapped in glass getting water in it and rotting the inside. A steel hull or solid glass would be best, I don’t know what makes. Thank you🇺🇸


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## Barquito (Dec 5, 2007)

Production boats are mostly solid fiberglass. There are some that have balsa cored hulls. Home built hulls are often built using epoxy and glass sheathing over plywood. You may even find ferro-cement boats, steel hulled boats, aluminum boats. Any of these boats that has been well kept could be a good choice. All are a compromise of some sort.


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## JimsCAL (May 23, 2007)

Two makes that commonly use(d) cored hulls are C&C and J-Boats. Just about all have cored decks.


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## zeehag (Nov 16, 2008)

lafitte 44 is foam cored. many new fangled cruisers are cored fg hulls. pre 1975 solid heavy deeep keeled cruisers are solid. yorktown, formosa, ct, cal, .... and many others are solid fg hull construction. best o luck in your search.


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## Jeff_H (Feb 26, 2000)

Irv775 said:


> Does any know what Sailboats have solid fiberglass hulls? I fear an older boat with plywood wrapped in glass getting water in it and rotting the inside. A steel hull or solid glass would be best, I don't know what makes. Thank you??


There are very few boats out there with plywood coring in the deck, and I know of no production model with plywood coring in the hull except maybe the Newporter motor sailer which was essentially a wooden boat with glass sheathing.

There is a lot of misinformation out there on cored hulls. First of all, coring a hull is much more expensive than building a solid hull and so was typically done on higher quality boats. For this reason the vast majority of production boats have un-cored hulls.

While early cored hulls were more likely to be prone to having core rot, over time the later built cored hulls reduced the likelihood of having coring issues through a number of effective strategies.

Cored hulls tend to have much greater bending strength and better puncture and fatigue resistance than un-cored hulls and so start out stronger and retain a larger percentage of the original strength over the life of the boat.

Often un-cored hulls were built thicker to try to achieve the stiffness of a cored hulls. This thickness was typically achieved by the use of non-directional reinforcement fabrics, which greatly reduced the puncture and fatigue resistance of the laminate; resulting in hulls which counterintuitively are much weaker and damage prone than one might otherwise assume, a condition that worstens over time. The greater weight of a un-cored hulls means that they typically encounter high stresses and larger impact forces. It also means that they typically have some mix of less stability, lower performance, less carrying capacity, a poorer motion comfort, and compromised seaworthiness as compared to a similar design with the same displacement but with a cored hull.

Except for ferrocement, steel has the least strength per pound of all of the typical boat building materials. There are strategies that help with corrosion but even so, steel boats tend to require more attention than other boat building materials except for conventional wood construction.

The greater weight of steel boats results in the same mix of compromises as a solid core hull but to a much greater extent than the un-cored hulls. Often lighter plating is substituted as a way of reducing weight, but that comes at the price of reduced strength in a range that is well below that of a cored hull and even that of an un-cored hulls.

The only real advantage of a steel hull is greater abrasion resistance. Some steel boats also have steel decks. Steel decks reduce the opportunity for leaks to occur but at the price of decreased stability and motion comfort.

Jeff


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## MikeOReilly (Apr 12, 2010)

My 1977 Rafiki 37 has a airex cored hull down to near where the keel begins. I’ve never heard of any issues with the hulls of these boats; certainly nothing with mine.


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