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Fibreglass composites – properties and applications

What GRP is made of and when it may be suitable.
March 2, 2026 by
Fibreglass composites – properties and applications

TECHNICAL ARTICLE

Glass-fibre composites combine glass reinforcement with a polymer binder. The material can provide low weight and resistance to corrosive environments. Its suitability for a structure depends on the material construction, loading and exposure.

What do GRP and GFRP mean?

GRP and GFRP refer to glass-reinforced plastic or glass-fibre-reinforced polymer. The fibres contribute strength and stiffness. The resin binds the fibres, transfers forces and protects the reinforcement. FRP is a broader term that also covers other reinforcement fibres.

Fibre orientation, fibre content, resin and manufacturing method affect performance. There is therefore no single strength, chemical resistance or temperature limit that applies to every GRP product.

Glass fibres before further processing
Glass fibres before further processing
Pultruded GRP grating
Pultruded GRP grating

Properties in practical use

  • Low weight: can reduce dead load and simplify transport, handling and installation.
  • Corrosion resistance: GRP does not rust like steel, but chemicals, moisture, UV and temperature can affect the resin and fibres.
  • Directional properties: fibre orientation and load direction need to be considered together, particularly for structural profiles.
  • Electrical properties: suitable systems can provide insulation, but performance must be documented for the product and application.
Stairs in an industrial structure
Stairs in an industrial structure
Detail of grating with a contrasting edge
Detail of grating with a contrasting edge

Resin selection and fire requirements

Polyester, vinyl ester and phenolic systems can provide different properties. Selection must reflect actual exposure and available documentation. A resin name is not a guarantee of resistance to every chemical.

Glass fibres and the polymer behave differently in a fire. A GRP product is not automatically non-combustible or self-extinguishing. Flame spread, smoke and any load-bearing requirements during fire must be checked against relevant product test results.

GRP structure at a facility
GRP structure at a facility
Machining a component in the workshop
Machining a component in the workshop

From material to installed system

Applications include grating, structural profiles, walkways, platforms, handrails and piping. Glassfiber Produkter connects product selection with engineering, fabrication, delivery and installation. Our GRP construction systems illustrate how components can form complete solutions.

Working on a component in the workshop
Working on a component in the workshop
Walkway between tanks
Walkway between tanks

Service life and maintenance

Correct material selection can reduce corrosion-related maintenance. It does not remove the need to inspect surfaces, joints, fixings and loaded areas. Cleaning and repairs should follow the product documentation and operating conditions.

An environmental comparison must assess the specific solution over its life cycle, including raw materials, manufacture, transport, use and end-of-life handling. Low weight or a long expected service life alone does not establish a lower overall environmental impact.

Lifting and installing a structure
Lifting and installing a structure
Stair treads and handrails
Stair treads and handrails
Access structure beside tanks
Access structure beside tanks
Detail of grating and handrails
Detail of grating and handrails

When should GRP be considered?

Start with the function: spans and loads, exposure, temperature, fire requirements, surfaces and installation. Compare possible materials on the same basis. Explore our solutions for examples, or send the project requirements for an assessment.

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