Wooden Boat Restoration Repair - WEST SYSTEM Epoxy

1.4.3 Ventilating for longevity
Introduction 7
Encapsulating an older or conventionally built boat is not possible unless all of the
surfaces, especially the contact surfaces of joints, can be coated. This would involve
disassembling the boat, piece by piece, and bonding it back together. You’ll have to
decide if your boat is worth this much effort. However, even if you cannot encapsulate
the entire boat, you can look for structural units that might be encapsulated. You might
be able to encapsulate some areas by removing and bonding one piece at a time
“Can I coat the inside of my boat with epoxy?” is a question often asked. In most cases,
you are better off not coating the interior. Just to coat as many surfaces of the interior
as you can reach leaves many un-coated surfaces and is not the same as encapsulating
since it does not ensure a continuous unbroken moisture barrier and will not eliminate
joint movement or prevent moisture from entering a joint. Failing to coat the
inaccessible contact surfaces of joints can create ideal environments for dry rot if there
is a leak. So keeping the interior well ventilated is often a better solution than
attempting to coat areas that may trap moisture. The object is always to deny at least
one of the four conditions necessary for rot to survive, in this case keeping the wood
moisture content below the saturation point. If you can’t guarantee keeping water out
of the structure, the next best option is to guarantee that it is not trapped in.
What about coating the exterior of the hull? If you eliminate movement between the
hull planks by bonding them together, coating the exterior of the hull is a good idea.
When the framing is sound, edge-bonding the planking, coating the exterior and
ventilating the interior is a good intermediate repair. It adds a lot of stiffness to the
structure, eliminates a source of moisture entering the boat and, when the boat is
properly ventilated, does not trap moisture in the boat.
Ventilation is the key to the continued longevity of your boat. No boat is
maintenance-free. Either you consider preventive maintenance or you accept periodic
rebuilding and repair. All boats—wood, fiberglass, aluminum and steel—need good
ventilation. Keeping the boat’s interior as dry as possible is the best preventive
maintenance for preserving the structure and making the boat more comfortable.
Clean bilges, an open interior layout, watertight deck openings and effective
ventilators all work together to provide good ventilation. If you have questions about
options, we suggest you consult the books on boatbuilding, outfitting and storing your
boat listed in Appendix–Additional reading, page 77.
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