Material · Technology · History

What is GRC

Definition

A high-performance
mineral composite

GRC (Glass Fibre Reinforced Concrete) or GFRC (Glass Fiber Reinforced Concrete) is a Portland cement–based mineral composite to which fine aggregates and alkali-resistant (AR) glass fibres are added, either distributed within the mix (Premix) or sprayed onto the mould by Spray (pneumatic spraying).

GRC was born in the early 1970s in Europe, as the result of research aimed at overcoming the problems of asbestos. Since then, its applications have flourished in the world of architectural creativity thanks to its ease of manufacture with great freedom of form.

Conventional glass fibres have no resistance to the alkalis in cement. The key to GRC was the development of an alkali-resistant glass fibre capable of retaining its mechanical properties in permanent contact with cement.

GRC panel types

Technical properties

Why GRC is
an exceptional material

1.800-2.100
Kg/m³ · GRC specific weight

Extreme lightness

Compared with 2,400 kg/m³ for conventional concrete. Thicknesses of 10–15 mm. Monumental façades without overloading the structure.

15-25
MPa · Flexural strength

High flexural-tensile strength

GRC performs well in tension thanks to the AR fibres, far exceeding the 3–5 MPa of conventional concrete.

50+
Years of proven research

Proven durability

Over 50 years of building-façade installations worldwide have demonstrated that, when properly specified and manufactured, GRC withstands seismic movements and hurricane-force winds.

A1
Fire reaction · UNE-EN 13501

Non-combustible

100% mineral material. A1 classification, the highest. Compliant with all high-rise building façade regulations.

800
kg/m³ of cement in the matrix

Low permeability

achieved through silicate coatings or glazes, which may be colourless or pigmented. Recommended for façades exposed to polluted atmospheres.

∞
Freedom of form

Any geometry

Curves, reliefs, stone-like textures and bespoke finishes. The only limitation is the demould­ability of the piece.

Comparison

GRC vs conventional concrete

Feature GRC Conventional concrete
Specific weight 1.800-2.100 Kg/m³ 2.400 Kg/m³
Minimum thickness 10–13 mm 60–70 mm
Flexural strength 15-25 MPa 3–5 MPa
Freedom of form Very high High
Industrial precasting Optimal Adequate
Fire reaction A1 (non-combustible) A1 (non-combustible)

History

Half a century of evolution

70s
Birth in Europe. Initial research by Pilkington to find an alternative to asbestos. Development of alkali-resistant (AR) glass fibre.
80s
Global expansion. GRC is refined in the USA and Japan. FORTON develops polymer additions that enhance durability.
90s
European standardisation. Drafting of the first European standards (CEN TC178). Consolidation of GRC as a premier façade material.
2000s
High Performance GFRC. "High-performance" GRC variants (UHQGRC, HP-GFRC) emerge with substantial improvements in durability and mechanical strength.
2010s
Nanotechnology and photocatalysis. Addition of nano-titanium dioxide for self-cleaning and depolluting properties.
2020s
Convergence with UHPFRC. Lafarge-Holcim investigates the similarities between GRC and UHPFRC. The diversity of possible formulations opens a technical debate that the authors address in the Compendium.

Want to go deeper?

The reference compendium on GRC and UHPFRC

9 chapters and over half a century of the authors' hands-on experience. In Spanish.

View the Compendium (€85 + VAT) GRC Types →