GB 46028-2025 has now officially taken effect. Compared with earlier recommended standards such as JC/T 908 Artificial Stone, the new national standard presents three fundamental changes in its indicator system:
- From recommended to mandatory: indicators such as flexural strength and frost resistance have moved from “suggested values” to “admission values”;
- From vague to clear: inorganic-based synthetic stone has received an independent technical indicator system for the first time, no longer mixed into the broad “artificial stone” category;
- From general to precise: inorganic-based synthetic stone has, for the first time, a complete set of independent indoor and outdoor technical indicators.
Interpretation of key indicator changes
Flexural strength: from industry recommendation to mandatory threshold
Key takeaway: Previously, “flexural strength ≥15 MPa” was the general requirement of JC/T 908 Artificial Stone for interior panels. The new national standard instead establishes a dedicated flexural threshold for dry-hung scenarios: inorganic-based artificial stone must reach ≥10 MPa — the basic safety baseline for dry-hung installation.
Panel thickness: new rules for exterior dry-hung
Key finding: Inorganic-based synthetic stone for the first time has a complete set of indoor/outdoor dry-hung technical indicators — interior ≥20mm, exterior ≥25mm, consistent with the requirements for granite. According to the drafting notes of GB 46028-2025: “The strength indicators of inorganic-based synthetic stone exceed those of granite; indoor and outdoor applications follow the minimum thickness requirements of granite.”
Frost resistance: a new hard indicator for exterior dry-hung
Key takeaway: Previously, frost resistance was only required by some local specifications; it is now elevated to a mandatory national standard indicator. For exterior stone projects in northern regions, this is a hard threshold that must be met.
Adhesives: new bond strength requirements
Stone adhesives must also comply with mandatory standards including GB 30982 Limit of Hazardous Substances in Building Adhesives and GB 33372 Limit of Volatile Organic Compounds in Adhesives.
Why is the new standard a “watershed”?
- Before: industry standards were recommendations, local specifications varied, and compliance requirements were vague. Companies could choose selectively, clients found it hard to judge, and the market was mixed.
- Now: one mandatory national standard unifies the admission threshold. You either meet it or you don’t.
For inorganic-based synthetic stone, the new standard is a major positive:
- It gains an independent technical indicator system parallel to natural stone for the first time.
- Its exterior dry-hung technical indicator system is now parallel to granite.
- The ≥10 MPa flexural threshold keeps manufacturers without sufficient technical strength out of the market.
The new standard is not the end, but a new beginning. Whoever can prove not just compliance but over-compliance will seize the initiative in the new-standard era.
This article is compiled from the original text of GB 46028-2025, issued by the State Administration for Market Regulation and the Standardization Administration of China on August 1, 2025, and effective August 1, 2026.