Flowcoat

A pigmented, resin-rich surface coat applied to the mould face before laminating, which cures to form the smooth, weather-resistant outer surface of a GRP moulding. It protects the underlying laminate from moisture and UV exposure and provides the colour and gloss of the finished part.

A composite of glass fibre reinforcement in a polymer matrix, most commonly polyester or vinyl ester resin. GRP is widely specified for boat hulls, tanks, enclosures, cladding and cold-applied flat roofing thanks to its corrosion resistance, mouldability and moderate cost.

A non woven glass reinforcement made from chopped strands distributed randomly and held with a powder or emulsion binder that dissolves in styrene based resins. It gives roughly equal in plane properties in all directions, wets out readily by hand lay up and is the standard reinforcement in GRP flat roofing laminates. It is specified by areal weight.

A thermosetting resin dissolved in a reactive monomer, usually styrene, that cures by free-radical polymerisation when initiated with an organic peroxide such as MEKP. It is the workhorse matrix for glass-reinforced plastic in boat building, GRP roofing, tanks and vehicle panels, offering low cost and straightforward processing.