Because of their buoyancy, polystyrene and polyurethane foams are widely used in the marine industry. Some of the typical uses of these foams include:

Pontoons - Polystyrene foam is often used as the core material in pontoons, while Polystyrene foam can be used for both concrete and vinyl encasing of pontoons.

Refrigeration - Polystyrene and polyurethane foam are insulators and are often used in freezer or coolers in boats.

Boating - Polystyrene and polyurethane foam are used as buoyancy providers by boat builders. Both styrene and urethane can be cut to size, to fill exact boat specifications. Polyurethane is resistant to solvent attack, so it is ideal for surveyed craft.

Baffles - Flotation baffles are used when containing spills on the water. Australian Urethane & Styrene supplies polystyrene and polyurethane for use as cores in baffles.