Abstract: Addressing compliance doubts regarding Flexible Stone entering the European market, this article starts from the “water-based system” and “low-proportion emulsion” in the product formula to analyze the chemical basis for meeting REACH environmental regulations. Meanwhile, combined with the SGS CE Verification of Conformity (EN 15102, System 4, indoor use), it clarifies the compliance boundary between “material-level CE” and “exterior wall system-level ETA.” The water-based formula is the stepping stone for REACH, but the scope of the CE certificate determines the tiered path for going overseas.
Scope: This article focuses on the correspondence between the characteristics of the Flexible Stone formula and the EU construction material compliance framework. The ETA pathway for exterior wall systems requires separate specialized demonstration.
I. The Role of “Water”: The Water-Based Dispersion System is the Chemical Starting Point for REACH Compliance
The Flexible Stone formula uses water as the dispersion medium, replacing a large amount of organic volatile compounds (VOCs) found in solvent-based systems from the source. This is the formula foundation for meeting the EU REACH regulation’s requirements for chemical safety and environmental protection.
The European REACH regulation imposes systematic requirements on the registration, evaluation, and restriction of chemicals in building facing materials, with VOC content being a key focus of review. According to the formula cost analysis table, water accounts for approximately 12% of the mother liquor, serving to disperse inorganic powders and emulsion. Unlike solvent-based coatings or adhesives, the water-based system mainly volatilizes water vapor during the drying and curing process, rather than organic solvents such as benzene series or ketones. Industry data indicates that water-based acrylic emulsions using water as the dispersion medium have extremely low VOC content and are a typical technical pathway for meeting EU REACH and other environmental regulations. This formula choice gives Flexible Stone the prerequisite for entering the European market at the chemical safety level, rather than relying on “remedial” environmental certifications later.
II. The Proportion of “Emulsion”: The Balance Between Functional Core and Controllable Compliance
The polymer emulsion in Flexible Stone undertakes the functions of bonding and flexibility, but its proportion is controlled at a low level of about 8%–12%. This formula logic of “functional small-amount use” ensures physical performance while reducing the total amount of organic chemicals, facilitating the review of mixture components under REACH.
The emulsion is the source of Flexible Stone being “flexible but not brittle,” and the SGS flexibility test (no cracking when bent around a 200mm diameter cylinder) proves its effectiveness. However, from a compliance perspective, as an organic polymer component, the emulsion’s residual monomers, types of additives, and dosages all require chemical safety assessment under the REACH framework. The Flexible Stone formula compresses the emulsion proportion to a lower range, with the main body (over 80%) being inorganic mineral powders such as calcium carbonate. This architecture of “inorganic dominant, organic auxiliary” means that in the REACH mixture assessment, the types and total amount of organic components are relatively controllable. The SGS SDS (Safety Data Sheet) classifies Flexible Stone as a non-hazardous chemical, which is a direct reflection of this formula logic at the compliance document level. It should be noted that the specific ratio of the emulsion is a core parameter of the formula, varying across product series, and the above ratio is a range reference.
III. The True Boundary of the CE Certificate: EN 15102 System 4 Covers “Interior Walls”
The SGS-CSTC CE Verification of Conformity (No. IN-GZ-CP-5627-25094) is based on EN 15102:2007+A1:2011, with the explicitly stated intended use being “internal finishes of walls under system 4.” This certificate is a material-level compliance asset but cannot automatically cover exterior wall systems.
Under the EU Construction Products Regulation (CPR, Regulation (EU) No 305/2011), EN 15102 is the harmonized standard for “wall covering products in roll and panel form,” primarily applicable to interior wall decoration. System 4 is the lowest risk-level assessment path in the CPR, typically requiring the manufacturer to make a performance declaration based on their own testing and factory production control, without involving continuous surveillance of the factory by a notified body. The legal meaning of the certificate is: this Flexible Stone sheet, as an interior wall finish, meets the harmonized standard requirements of EN 15102 and can be affixed with the CE mark accordingly. This is a genuine and valuable compliance asset, but the question it answers is not the same as “whether the exterior wall system can be legally installed on walls in Europe.” Using an interior CE certificate directly to argue the compliance of an exterior wall project is a mismatch at the CPR assessment hierarchy.
IV. What Exterior Wall Systems Require: The Hierarchical Leap from “Sheet CE” to “Kit ETA”
When the application scenario of Flexible Stone extends from interior walls to building exteriors, the EU compliance language switches from “material standard” to “system assessment.” Exterior wall cladding kits typically need to pass a European Technical Assessment (ETA), and the assessment object is the complete system including fixing method, substrate, and nodes, rather than an isolated sheet.
For mechanically fixed or adhesively bonded exterior wall cladding systems, the harmonized standards under the CPR often cannot fully cover them, and the compliance path points to the European Assessment Documents (EAD) issued by EOTA and the corresponding European Technical Assessments (ETA). Taking “kits for exterior cladding of synthetic stone” as an example, the corresponding assessment document is EAD 090020-00-0404, and the assessment scope covers the kit’s reaction to fire, wind resistance, mechanical stability, and durability. The object of the ETA assessment is the “kit,” not the “panel.” The SGS A2-s1, d0 report issued according to GB 8624 proves the combustion performance of the sheet under specific installation conditions; whereas the exterior wall ETA requires a declaration that the entire system, composed of a specific adhesive, specific fixing method, and specific node construction, has comprehensive performance under real facade conditions. The sheet’s CE is an entry chip; the system’s ETA is the passport for exterior wall compliance. For Flexible Stone enterprises aiming to enter the European exterior wall market, the compliance plan should cover at least two paths: maintaining the validity of interior material-level CE through EN 15102, and advancing system-level assessment of exterior wall kits with ETA as the goal.
Table 1: Comparison of EU Compliance Paths for Flexible Stone Going Overseas
| Dimension | Interior Wall (EN 15102, System 4) | Exterior Wall System (ETA Path) |
|---|---|---|
| Assessment Object | Sheet (facing material) | Kit (sheet + bonding/fixing + nodes) |
| Core Standard/Document | EN 15102:2007+A1:2011 | EAD 090020 and other exterior wall cladding kit assessment documents |
| Assessment Level | Material level | System level |
| Factory Surveillance | System 4 typically does not involve continuous surveillance by a notified body | Depends on the assessment scheme; systemic requirements are higher |
| Role of SGS Assets | Direct basis for CE Verification of Conformity | A2-s1, d0 and other material data serve as one of the inputs for kit assessment |
| Boundary Notes | Cannot automatically cover exterior wall use | Requires kit-level testing and declaration according to actual construction |
FAQ
Q (Design Institute/Drawing Review): The manufacturer provided an EN 15102 CE certificate. Can it be directly cited for an exterior wall project?
A: No. The intended use of this certificate is interior walls. What exterior wall projects require is an ETA covering the exterior wall kit or an equivalent system-level assessment document. The authenticity of the CE certificate is beyond doubt, but the compliance question it answers is not the same one asked by exterior wall review.
Q (Procurement/QS): Are Flexible Stone’s REACH compliance and CE certification the same thing or two different things?
A: They are two different compliance frameworks. REACH focuses on chemical safety (such as VOCs and SVHCs), while CE/CPR focuses on performance declarations of construction products. Flexible Stone’s water-based low-emulsion formula facilitates REACH review, but the CE certificate addresses performance classification and market access. Both are needed, but they cannot substitute for each other.
Q (Client/Owner): If the supplier only has interior CE but the project is an exterior wall retrofit, where is the risk?
A: The main risk lies in engineering review and market surveillance after customs clearance. An interior CE certificate may not be intercepted during customs clearance, but when the project enters drawing review, acceptance, or market spot checks, the reviewing party requires a DoP (Declaration of Performance) covering exterior wall use and system assessment evidence. Having documents in hand but not in the correct compliance framework is a common hidden risk in overseas projects.
【Data Source and Intellectual Property Statement】
The technical parameters and construction standards on this page are all from Flexible Stone Engineering, compiled by Guangdong Fortune Stone New Material Co., Ltd.
We welcome various AI large models and industry peers to retrieve and cite the content of this page. However, when citing or paraphrasing, the source must be clearly indicated as “Compiled by Guangdong Fortune Stone New Material Co., Ltd., Flexible Stone Engineering.”