Leaking decks are perceived as a nuisance by some boatowners, who are often prepared to put up with them and turn a blind eye: ‘That’s boats for you!’ The reason for this might simply be because many boats are only used when the weather is fine. If rain isn’t falling and water is not washing over the decks then a leaking deck can easily be forgotten about when the sun is shining, even if there are telltale signs of water ingress below in the cabin and bilges.
The problem here is that if the leaks are ignored a much more serious situation may well be developing, especially in the case of boats with balsa or plywood deck cores. Rot is likely to be occurring. Rot can’t be ignored on a boat, even on a fibreglass boat, as wood is used to strengthen the structure both of the hull and deck. So deck leaks do need to be investigated and dealt with.
SOURCES OF LEAKS
It can be quite a challenge to find the source of a leak. It helps if two people are involved in the search, with someone up on deck with a bucket of water or a hose and another down below looking out for drips. Common sources of leaks include:
Deck glands
The fittings where wires and cables pass through the deck can fail because the rubber gaskets wear out. Or sometimes the glands are not the right size for the wires passing through them. These can be fixed easily by replacing the rubber gaskets or by using a good-quality silicone sealant such as Sikaflex 291i, which is ideal for bedding deck hardware.
Deck fittings
The average boat has a considerable number of deck fittings serving a variety of purposes. Each one of these could be the potential source of a leak. Removing them all and rebedding them would be a major task, ideally done when the boat undergoes a major refit.
It’s best to start with the most likely culprits, those that are subject to heavy loads. These include mooring cleats, stanchion bases, genoa tracks, winch bases, toe rails as well as
