GRC, a term frequently heard in the precast sector, is an abbreviation derived from the first letters of Glassfibre Reinforced Concrete, which can be defined as concrete reinforced with fiberglass. It is a durable and long-lasting building material that stands out with its properties.

Essentially consisting of 4 main components; white Portland cement, silica sand containing high silica content, alkali-resistant fiberglass, and water. Depending on the dimensions of the structure to be produced, plasticizers and other chemicals can also be used.

GRC Features

Especially in recent years, GRC, whose usage is increasing, attracts attention with its unique features. When we look at the features of GRC;

  • It is composed of 4 main components.
  •  It shows higher resistance to impact and compression compared to traditional concretes.
  • It has a lightweight structure, which provides significant convenience to workers during production, transportation, and assembly stages.
  • It is one of the most resistant materials against earthquakes.
  • It provides sound insulation and is also waterproof.
  • In addition to its durable structure, it offers rich design options aesthetically.
  • GRC, which can be preferred in almost all exterior facades, has a wide range of applications.
  • It is poured into the mold through two different methods: casting or spraying system.

How is GRC Made?

There are two techniques in GRC production methods. These two methods, which can be called premix and spray technology, vary according to the area where the application will be made. The method of pouring the mixture obtained with multiple components into the mold is called premix.

In addition, in the Spray method, the material is applied by spraying with a special device. In the premix method, generally, the material produced is filled inside. When filled material is desired to be used, the premix method is preferred.

Three different types of molds are used in GRC concrete applications. Mold selection is important for efficient use. By selecting molds suitable for decorative designs, cost savings can be achieved. Mold types are three: wood, polyester, and silicone. Wood and polyester molds are frequently preferred in exterior facade applications, and silicone molds are also used in areas requiring special applications.

GRC Connection Types

There are 2 different connection types in GRC precast facade claddings: Pedestal or Framed connections.

Q8 steel bars are used in both connection types. These bars, called flex bars, absorb earthquake loads. The frames that create the connection points are placed inside the mold while GRC precast is still wet. In GRC-Fiberton frames, profiles under 2.5 mm are not preferred due to the high heat generated during welding.

Use of GRC Concrete in Our Country

Our country, located in the earthquake belt, shows sensitivity to this issue in the structures created. Resilient building materials against earthquakes, seismic shaking, and damage are preferred not only in the entire structure but also in the exterior facades.

The use of GRC Concrete in our country, with its lightweight and durable structure, has been increasing in recent years, and GRC Concrete application stands out. Because GRC, which saves from the weight of external walls added to buildings, also attracts attention with its rich designs.

Our company, which provides the most successful services in precast facade, creates durable designs that meet expectations and needs. Beonsan, using special techniques and materials, delivers the applications it produces smoothly.

Physical Properties


Compressive Strength c: 45-70 N/mm²

c: 45-70 N/mm²

Tensile Strength fct: 5-9 N/mm²

fct: 5-9 N/mm²

Yield Strength LOP: 6-8 N/mm²

LOP: 6-8 N/mm²

Modulus of Rupture MOR: 14-24 N/mm²

MOR: 14-24 N/mm²

Expansion Limit eu: 0.5-4 %

eu: 0.5-4 %

Elastic Modulus E: 11-17 kN/mm²

E: 11-17 kN/mm²

Density 1.7 – 21 kg/dm³

Dnsity 1.7 – 21 kg/dm³

Expansion T: 1.0 – 15 X 10-5

T: 1.0 – 15 X 10-5

Thermal Conductivity 0.8 – 1.3 W/mk

0.8 – 1.3 W/mk

Fire Resistance (DIN 4102) A1

(DIN 4102) A1

Shrinkage Value Є cs : 1.0 – 2.0 mm/m

Є cs : 1.0 – 2.0 mm/m

Water Absorption 4-14 %

4-14 %

Water Vapor Diffusion µ : 50 – 200

µ : 50 – 200

Bilgi Al