What Are the Core Performance Differences Between GRC and GRG? An In-Depth Analysis of Material Essence and Application Divisions

GRC (Glass Fiber Reinforced Cement) and GRG (Glass Fiber Reinforced Gypsum) have similar names, and both are reinforced with alkali-resistant glass fiber, but the difference in their core cementitious materials leads to fundamental differences in performance, application scenarios, and process requirements. Qinglong Group, as a manufacturer proficient in both materials, summarizes their core differences as follows.

1. Cementitious Material and Water Resistance: This is the most fundamental difference. GRC uses cement as its cementitious material and is a hydraulic material with excellent water resistance, suitable for direct use outdoors and in humid environments. GRG uses high-strength gypsum (α-hemihydrate gypsum) as its cementitious material and is an air-hardening material with poor water resistance; it softens and loses strength when exposed to water or sustained high-humidity environments. Therefore, GRG is in principle limited to indoor dry environments.

2. Mechanical Properties: GRC offers higher compressive strength, flexural strength, and toughness, enabling the production of large-sized, thin-walled components with demanding load-bearing requirements. GRG's compressive and flexural strengths are typically lower than GRC's, but its impact resistance (toughness) is also excellent in dry environments, and it has better micro-deformation capacity, allowing it to shape extremely intricate relief details.

3. Surface Finish and Workability: GRG products have smoother, finer surfaces and can easily achieve extremely high detail fidelity and a smooth texture through molds, making them commonly used in high-end interior decoration. GRC surfaces are relatively rough, but can achieve very good results after treatment, and GRC can be molded into a richer variety of textures, such as faux stone and faux wood.

4. Fire Resistance: Both are Class A non-combustible materials. However, GRG releases crystalline water at high temperatures, providing a certain fireproofing and thermal insulation effect.

5. Self-weight: Gypsum has a lower density than cement, so for the same volume, GRG products are lighter than GRC.

Application Selection Guide: Simply put, choose GRC for "outdoor, humid, structural, large-scale" applications, such as building facades, roofing, landscape components, and noise barriers. Choose GRG for "indoor, dry, high-detail, custom-shaped ceilings and walls", such as complex ceilings in theaters/hotels, artistic reliefs, and wall decorations. Inside the Nanning Culture and Arts Center, we used GRG extensively to create streamlined ceilings, while its exterior features a GRC curtain wall, each material leveraging its own strengths.