Which material is strong, lightweight, and an insulator, used for water tanks, surfboards, and boats?

• A. Glass Reinforced Plastic (GRP)
• B. Composite
• C. Glass
• D. Epoxy Resin

Answer: (A)

Glass Reinforced Plastic is a composite where glass fibers are embedded in a plastic resin. The glass fibers carry most of the load, giving high strength and stiffness while keeping the material light. The resin binds the fibers, provides a smooth, waterproof outer surface, and acts as an electrical and thermal insulator. This combination makes the material strong for its weight, resistant to water and corrosion, and easy to shape into hulls, boards, or tanks.

For water tanks, you get a non-corroding, watertight container that won’t rust. For surfboards, the lightweight yet stiff construction gives good buoyancy and performance. For boats, the strong, lightweight hulls resist marine exposure and remain easier to manufacture in complex shapes. Epoxy resin alone is not a structural material, and glass by itself is brittle and heavy; a generic “composite” is too vague for these specific applications. This is why Glass Reinforced Plastic best fits the description.