top of page

What is grc?

Glass-Fibre Reinforced Concrete, commonly known as GRC, is a high-strength composite stone. At its core, it is a blend of cement mortar (a combination of cement, sand, and a polymer) that's reinforced with alkali-resistant glass fibres.


Traditionally, concrete is known for its robustness against compression, but it can be quite weak against tension. To combat this, reinforcement is typically added to the mix. Precast concrete, for instance, is reinforced with steel. However, this can make the resultant products excessively heavy due to increased thickness.


This is where GRC shines. The glass fibres incorporated into GRC not only enhance the strength of the material but also significantly lighten it. These alkali-resistant fibres serve as the main tensile load-carrying component. Simultaneously, the polymer and concrete matrix binds these fibres together, facilitating load transfer from one fibre to another. This synergy results in a material far stronger and more resistant to breakage and cracking than traditional concrete.


Though GRC is classified as 'concrete', the term can be slightly misleading. That's because the infusion of glass fibres into the mix vastly improves the product's strength, while dramatically reducing its weight. This lightweight characteristic of GRC makes it safer and more convenient to handle on-site. Furthermore, it reduces the load on structures when installed, enhancing the overall safety and longevity of the built environment."

GRC Fibreglass Chopped .jpg



All our products are designed and manufactured specifically for New Zealand conditions. In most situations the furniture can be placed on deck and balcony surfaces as it can usually be lifted by 2 able people, although heavy enough to withstand the strong coastal and alpine conditions that New Zealand offers.

The Advantages and Benefits of GRC


GRC can be moulded to accurately reproduce almost any small or large shape



GRC products can be manufactured using different cements (e.g. white, off-white, grey), that can be coloured with oxide.


Impact Resistant

GRC products are highly durable.They will not shatter upon impact, and any localised damage can usually be repaired.



GRC will not rust or rot, needs no painting, and because it contains no steel, it will not corrode or expand. GRC does not suffer from traditional concrete issues.


Water Resistant

GRC is virtually impermeable to water thus making it ideal for products such as planters and water features. Usually, no additional waterproofing is required.

Chemical Resistant

The high density and high cement content of GRC give a higher chemical resistance than other cement-based materials.


Fire Resistant

GRC does not burn or emit smoke when exposed to fire. This gives architects and designers greater flexibility in specifying components to satisfy for performance requirements.


Environmentally Friendly

The main constituents of GRC are based on the naturally occurring earth oxides that are used in the manufacture of cement and glass fibers. These are not generally regarded as pollutants.

Lower Carbon Foot Print

GRC has a much lower impact on the environment than traditional concrete or stone. It is designed to be long lasting and earth friendly. Its lightweight quality also speeds the transport and construction aspects of a project, also reducing the carbon footprint.

​The reduced weight of GRC compared to steel reinforced concrete products provides environmental benefits.  An assessment carried out as part of a UK government-DETR/Concrete Industry Alliance ‘Partners in Technology’ project compared two precast concrete and GRC products that fulfill the same function.

The results show that GRC has a lower environmental impact (around 40% less).  The main reasons for the reduced environmental impact of GRC compared to traditional precast concrete are:

  • Reduced cement usage per product

  • Reduced transport costs

All these advantages and benefits make GRC an ideal material for the manufacture of planters, planter boxes, street furniture, architectural mouldings and panels.

bottom of page