Ultimate Selection Guide for Four Major Decoration Materials: A One-Page Decision Tree for GRC, GRG, UHPC, and GRP

The four materials most frequently mentioned in modern architectural and interior decoration — GRC, GRG, UHPC, GRP — are often confused with each other, yet each has a distinct chemical basis, performance envelope, and ideal application. Choosing the wrong material leads to either budget overruns, premature failure, or both. Guangdong Qinglong Construction, drawing on 28 years of full-chain production and installation experience across all four materials, gives a single-decision-tree comparison and a "one-page" reference for specifiers.

1. What Each Material Is, in One Line Each

GRC (Glass Fiber Reinforced Concrete): cement + quartz sand + alkali-resistant glass fibre. For outdoor curtain walls and structural-grade cladding.
GRG (Glass Fiber Reinforced Gypsum): gypsum + glass fibre + additives. For indoor dry-zone ceilings, walls, and detailed mouldings.
UHPC (Ultra-High Performance Concrete): cement + silica fume + steel fibre. Compressive strength ≥ 120 MPa. For high-end, ultra-thin, signature façades.
GRP (Glass Fiber Reinforced Plastics / Fibreglass): polyester or epoxy resin + glass fibre. Light, mouldable, used for sculptural props, themed-park shapes, and some non-structural outdoor ornaments.

2. The Four-Material Comparison Table

Dimension	GRC	GRG	UHPC	GRP
Base chemistry	Cement (inorganic)	Gypsum (inorganic)	Cement + silica fume (inorganic)	Polyester / epoxy resin (organic)
Reinforcement	Alkali-resistant glass fibre	Glass fibre	Steel fibre (1–3% by volume)	Glass fibre
Typical wall thickness	12–25 mm	6–10 mm	8–15 mm (down to 6 mm in special cases)	4–12 mm
Density	1.8–2.0 t/m³	1.5–1.8 t/m³	2.4–2.6 t/m³	1.4–1.8 t/m³
Compressive strength	40–60 MPa	25–35 MPa	120–200 MPa	80–150 MPa (parallel to laminate)
Flexural strength	15–25 MPa	8–12 MPa	25–50 MPa	100–200 MPa (parallel)
Fire rating	A1 non-combustible	A1 (gypsum base)	A1 non-combustible	B-grade (typically); poor performance
UV resistance	High (inorganic)	Use indoors only	High (inorganic)	Limited; surface chalking after 5–10 years
Moisture resistance	High	Poor — indoor dry zones only	Very high (dense matrix)	Moderate; long-term moisture causes osmotic blistering
Service life (design)	50+ years	30–50 years (indoor)	100+ years	15–25 years
Cost (per m², complex shape)	RMB 600–2,000	RMB 500–1,200	RMB 2,500–5,000	RMB 400–1,500
Typical applications	Outdoor curtain walls, large mouldings, complex shapes	Indoor ceilings, detailed walls, classical mouldings	High-end landmarks, ultra-thin canopies, wet zones	Sculptural props, themed park shapes, signage

3. The One-Page Decision Tree

Use this four-step selection rule:

Is the application indoor or outdoor?
- Indoor dry → GRG or GRC (if impact-prone).
- Indoor with humidity (bathroom, pool adjacent) → UHPC or specially coated GRC.
- Outdoor general → GRC.
- Outdoor high-end / signature → UHPC.
- Outdoor sculptural prop / themed park → GRP (subject to fire and UV limits).
Is fire rating a hard constraint?
- Yes, A1 required (high-rise, public, escape route) → GRC, GRG, or UHPC. GRP is excluded.
Is the wall section ultra-thin or single-piece very long?
- Yes, under 10 mm or single-piece over 4 m → UHPC.
- No, conventional thickness acceptable → GRC or GRG.
Is the geometry a sculptural, organic, large-volume shape?
- Yes, and outdoor → GRC.
- Yes, and indoor → GRG.
- Yes, but only a prop or temporary exhibition → GRP (lowest cost, shortest life).

4. Common Misconceptions

"GRP and GRP-GRC are the same material.": GRP is resin-based (organic); GRC is cement-based (inorganic). Their chemistry, fire behaviour, and durability are completely different.
"UHPC is just a stronger GRC.": UHPC is a different cement composite with steel fibre reinforcement. The production equipment, moulds, curing regime, and installation skill set all differ.
"GRG is a budget compromise for GRC.": in indoor dry zones, GRG is the right material on its merits, not a cheap substitute. Its light weight and fine surface are the design intent, not a workaround.
"All four can be used anywhere.": their chemical differences make application boundaries non-negotiable. Use GRP indoors with low fire risk; never on a high-rise façade.

5. Common Hybrid Patterns

Premium projects almost always combine at least two of the four materials:

Indoor ceiling GRG + signature element UHPC: typical for hotel atriums.
Outdoor GRC main façade + signature UHPC entrance canopy: typical for Class A office towers.
Outdoor GRC permanent structure + GRP sculptural element: typical for theme parks where the GRP element is non-structural and replaceable.

6. Conclusion

The choice between GRC, GRG, UHPC, and GRP is a process of elimination driven by location, fire rating, structural demand, geometry, and budget — not a simple ranking. The four materials are complementary rather than competing: each is the right answer in its specific zone, and the most polished projects are those that combine them where each shines. Treating them as interchangeable is the first mistake to avoid.