Marine Classics
Marine Classics
Boat Designers
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Fibreglass Boats

We build fibreglass boats to a very high standard. Using materials which are  of a much higher quality than the majority of mass production boat builders, please read on to understand why.

Normal fibreglass is not absolutely water proof. Over time with continuous submersion water can penetrate the outer hard layer of gel coat and get into the structural layers.  This condition is known as 'Osmosis' and in severe cases will distroy the fibre glass and lead to hull failure and leakage. The cure for osmosis is the removal of the gel coat, area is then left to dry for a number of weeks and the gel coat re-applied.  Which is an inconvenient and expensive process.

This can be avoided with the use of epoxy resin, which when applied from new will prevent osmosis.  Most boat builders still do not do this, as the epoxy resin is much more expensive. But we do is as standard on all of our boats.

Fibreglass refers to a composite of fine glass fibres encapsulated in polyester or epoxy resin. The fibres have a high strength to weight ratio, and the resin is slightly elastic. By deforming slighly, the resin distibutes the forces  amongst the fibres,  so they work together.


Fibreglass is also called  GRP  - Glass Reinforced Plastic.
Corning Glass patented the term fibreglass in 1936, and DuPont was awarded a patent for polyester resin in 1936. By 1942 fiberglass aeroplane parts were being made. And the first succesful boats were made just after WW2.

However it wasn't untill the 1960's when fibreglass took over from wood as the major boat building method. Interestingly fibreglass didn't win because it is a better material - it has a lower strength to weight ratio than wood. In the very long term, it may not even last longer or be less maintenance than wood, because when the resin degades it cannot be repaired.

Fibreglass is actually the most common method for building mass production boats becuase it allows a reusesble a female mold to shape the boat. This allows semi-skilled labour to mould the hull of the boat very quickly and economically.

Fibreglass is strong in tension but not very stiff for it's comparatively heavy weight. So boats need to be made either of many layers of fibreglass (called solid fibreglass construction) or alternatively reinforced with wood or foam in order to provide stiffness (called sandwich construction).

 In sandwich hulls, a layer of wood, synthetic foam or balsa is applied after the outer layer of fiberglass is laid to the mold, but before the inner skin is laid. Early fibreglass boats were mostly of the solid construction type, up until around the early 1980's when sandwich construction  began to take over.