At Shanghai Danshang Technology Co., Ltd., the leading manufacturer of epoxy colored sand self-leveling floor coatings in China, we understand the growing demand for durable, decorative, and high-performance flooring systems across Africa, Asia, and worldwide. While epoxy flooring is widely recognized, it is important to note that no international standard currently exists for epoxy colored sand self-leveling paints and coatings.
To help our global clients apply these systems with confidence, we have translated and presented the T/SDDP 4-2021 Technical Specification and Industry Standard for Epoxy Colored Sand Self-Leveling Floor Construction, officially issued by the Shandong Flooring Industry Association. This standard serves as the authoritative guideline in China, providing detailed instructions on design, substrate preparation, construction procedures, and quality inspection.
By sharing this standard, our goal is to ensure that contractors, distributors, and project owners around the world can apply epoxy colored sand self-leveling floors according to recognized industry specifications, achieving both aesthetic excellence and long-term performance.
Preface
The T/SDDP 4-2021 Technical Specification and Industry Standard for Epoxy Colored Sand Self-Leveling Floor Construction was developed to provide clear guidelines for contractors, engineers, and flooring professionals. Drafted in accordance with GB/T 1.1-2020 and GB/T 20001.4, this standard ensures quality, safety, and consistency in the application of epoxy colored sand self-leveling flooring systems.
This standard was proposed and is governed by the Group Standard Committee of the Shandong Flooring Industry Association, a recognized authority in China’s flooring industry.
Drafting Organizations include:
- Qingdao Xiuper Technology Co., Ltd.
- Grund (Qingdao) New Eco-friendly Building Materials Co., Ltd.
- Qingdao Mingfeng Building Materials Co., Ltd.
- Qingdao Haigude Trading Co., Ltd.
- Qingdao Pengfeng Building Materials Co., Ltd.
Principal Drafters: Zhang Gongmin, Gong Changjun, Xu Guodong, Ji Yujun, Sun Xianlin
This is the first official release of the standard, marking a milestone in establishing recognized guidelines for epoxy colored sand self-leveling flooring.
1. Scope
1.1 This standard defines the design requirements and construction quality standards for epoxy colored sand self-leveling flooring systems. It provides a unified framework for the construction process, ensuring consistent performance and reliable results in real-world flooring applications.
1.2 The T/SDDP 4-2021 standard applies to new construction projects, renovations, and expansions, covering every stage from design and installation to quality inspection and final acceptance of epoxy colored sand self-leveling floors.
1.3 In addition to following this specification, all epoxy colored sand self-leveling flooring projects must also comply with current national flooring standards to guarantee safety, durability, and long-term performance.
2. Normative References
The following standards are referenced in T/SDDP 4-2021 Epoxy Colored Sand Self-Leveling Floor Construction Standard. These documents provide the technical foundation and ensure alignment with broader flooring engineering practices:
- CECS 328-2012 – Technical Specification for Integrated Flooring Engineering
- JC/T 2540-2019 – Terminology and Definitions of Flooring Materials
- JC/T 2570-2020 – Colored Sand Flooring Materials
- JC/T 2327-2015 – Waterborne Polyurethane Flooring
By referencing these established Chinese flooring standards, the Shandong Flooring Industry Association ensures that the T/SDDP 4-2021 specification is both comprehensive and compatible with existing flooring industry practices.
3. Terms and Definitions
3.1 Solvent-free Epoxy Resin Flooring Materials
High-performance resin-based flooring materials that use non-volatile organic compounds or reactive volatile organic compounds as the dispersion medium. These coatings are widely used in industrial and commercial projects where durability and safety are essential.
3.2 Waterborne Resin Flooring Materials
Environmentally friendly resin-based flooring materials that use water as the primary dispersion medium. This type of flooring is designed to reduce VOC emissions while maintaining strength and adhesion.
3.3 Colored Sand Self-Leveling Flooring Aggregate Grading
Artificially manufactured polymer aggregates designed and graded specifically for epoxy colored sand self-leveling floors. These aggregates enhance surface strength, decorative appeal, and long-term performance.
4. Marking
Products covered under the T/SDDP 4-2021 Epoxy Colored Sand Self-Leveling Floor Construction Standard shall be marked in the following order: product name, standard number, and category.
Example:
The marking for the Specification for Construction of Epoxy Colored Sand Self-Leveling Flooring is:
T/XXXX-20XX SL
Clear and consistent product marking ensures traceability, compliance, and quality assurance, which is especially important for international contractors and distributors.
5. General Provisions
5.01 Before starting the construction of an epoxy colored sand self-leveling flooring system, the concrete substrate must be thoroughly inspected. Based on the substrate acceptance report, a detailed construction plan shall be prepared, reviewed, and approved by the relevant parties. A technical briefing must also be conducted to ensure the project team follows the approved plan.
5.02 All materials used in the project must be supported with product quality certification documents. Their performance and quality shall meet or exceed the current national standards. In cases where no national standard exists, the materials shall comply with the requirements set forth in this specification.
5.03 The product quality certification documents shall include:
- 5.03.1 Product quality certificate and material test report
- 5.03.2 Technical quality indicators and test methods
- 5.03.3 Re-inspection reports or technical appraisal documents
5.04 Epoxy resin flooring materials must be stored in cool, dry, and well-ventilated environments, away from fire and heat sources. Outdoor storage and direct sunlight exposure are prohibited. The recommended storage temperature is 10°C–25°C to ensure product stability.
5.05 The construction unit shall establish strict inspection systems: self-inspection, cross-inspection, and designated personnel inspection for each process. Complete inspection records shall be maintained. For concealed works, inspection records must be signed and confirmed by the owner’s representative or supervisor before moving to the next stage.
5.06 The construction site must be fully enclosed, and cross-operations with other trades are strictly prohibited to ensure quality and safety.
5.07 During the construction of integrated flooring systems, adequate safety protection equipment shall be provided for both personnel and machinery.
6. Technical Requirements
6.1 Basic Physical Properties
6.1.1 The basic physical properties of epoxy colored sand self-leveling flooring materials shall comply with the requirements specified in Table 1, tested in accordance with GB/T 22374-2018 Floor Coating Materials.
Table 1 – Basic Physical Property Requirements
| No. | Item | Technical Requirement |
|---|---|---|
| 1 | Appearance | Liquid components must be uniform after mixing; colored sand must be free of clumps |
| 2 | Initial Flowability (mm) | ≥ 140 |
| 3 | Shore D Hardness | ≥ 70 |
| 4 | Tensile Bond Strength (MPa) | ≥ 2.0 |
| 5 | Compressive Strength (MPa) | ≥ 45 |
| 6 | Flexural Strength (MPa) | ≥ 20 |
| 7 | Abrasion Resistance (750 g/500 r) (g) | ≤ 0.025 |
| 8 | Slip Resistance (Dry Friction Coefficient) | ≥ 0.50 |
| 9 | Impact Resistance (1000 g, 100 cm) | No cracking, no peeling |
| 10 | Water Resistance (168 h) | No blistering, peeling, cracking, or discoloration |
6.2 Special Properties
For special applications, epoxy colored sand self-leveling flooring materials shall meet the basic requirements in Table 1 as well as the additional requirements in Table 2.
Table 2 – Special Property Requirements
| No. | Item | Technical Requirement |
|---|---|---|
| 1 | High Slip Resistance (Wet Friction Coefficient) | ≥ 0.70 |
| 2 | Chemical Corrosion Resistance | No blistering, peeling, or cracking |
| 3 | Artificial Weathering Resistance (400 h) | No blistering, peeling, or cracking; chalking ≤ Grade 1; discoloration ≤ Grade 2 |
| 4 | Stain Resistance | ≤ Grade 2 |
Notes:
a. Suitable for areas requiring high slip-resistance safety levels.
b. Suitable for environments exposed to strong acids, alkalis, and salts.
c. Suitable for outdoor applications.
d. Suitable for commercial and office environments.
6.3 Limits of Hazardous Substances
Epoxy colored sand self-leveling flooring materials shall comply with the solvent-free indicators specified in GB/T 22374. This ensures that the flooring system meets both environmental safety standards and health protection requirements, making it suitable for global projects in public, industrial, and residential spaces.
7. Structure of Epoxy Colored Sand Self-Leveling Flooring
7.1 The structural composition of an epoxy colored sand self-leveling flooring system is illustrated in Figure 1. Each layer plays a critical role in ensuring strength, adhesion, durability, and long-term performance.
Figure 1 – Structural Diagram of Epoxy Colored Sand Self-Leveling Flooring System
1 – Concrete Substrate: Provides the foundation for the flooring system.
2 – Epoxy Primer Layer: Enhances adhesion between the concrete base and subsequent coatings.
3 – Epoxy Mortar Intermediate Coat: Levels the surface and improves mechanical strength.
4 – Epoxy Colored Sand Self-Leveling Topping Layer: Decorative and functional layer, delivering durability, seamless finish, and slip resistance.
5 – Waterborne Polyurethane Topcoat: Protective finishing layer that improves chemical resistance, UV stability, and wear resistance.
8. Substrate Requirements and Treatment
8.1 Substrate Requirements
8.1.1 For epoxy colored sand self-leveling flooring systems, the concrete substrate must be solid, dense, and stable. The compressive strength shall not be less than 25 MPa; the average pull-off strength shall not be less than 1.5 MPa, with a minimum of 1.2 MPa. The substrate moisture content must not exceed 4% to prevent adhesion failure.
8.1.2 In addition to meeting the requirements of this specification, the substrate must also comply with the Code for Acceptance of Construction Quality of Building Ground Engineering (GB 50209).
8.2 Substrate Treatment
8.2.1 If the concrete substrate’s compressive strength is below 25 MPa, reinforcement measures must be taken, or the substrate should be reconstructed.
8.2.2 For cracks wider than 0.5 mm (excluding active, unstable, or water-seepage cracks), the proper method is filling and sealing. Cracks shall first be cut into V-shaped grooves (20 mm deep × 20 mm wide) by mechanical means, then filled with solvent-free epoxy resin.
8.2.3 When debonding occurs between the leveling layer and substrate:
- If the debonded area ≤ 1 m², it may be repaired by grouting.
- If the debonded area > 1 m², the leveling layer must be removed and reconstructed.
8.2.4 Surface defects such as dusting, laitance, or spalling must be removed mechanically.
8.2.5 Using a 2 m straightedge, if surface gaps exceed 3 mm, leveling treatment is required.
8.2.6 If the substrate contains an old coating, it must be completely removed by mechanical methods.
8.2.7 To enhance bonding strength, the substrate shall be treated by milling, shot blasting, or grinding.
8.2.8 For substrate moisture content:
- 4-8% → Ventilation, heating, or application of a moisture-blocking primer may be used.
- > 8% → A full moisture barrier layer must be applied.
9. Construction Process of Epoxy Colored Sand Self-Leveling Flooring System
9.1 Construction Sequence
The epoxy colored sand self-leveling flooring system shall be applied in the following sequence:
- Application of primer coat
- Trowel application of epoxy mortar intermediate coat
- Application of epoxy colored sand self-leveling topping coat
- Roller application of waterborne polyurethane topcoat
- Curing according to technical requirements
- Finished surface protection
9.2 Construction Requirements
9.2.1 The primer coat must be applied uniformly, with no omissions or excessive buildup.
9.2.2 The epoxy mortar intermediate coat shall be applied using a trowel. Local surface depressions may be repaired with resin mortar. Epoxy resin grouting material shall then be poured onto the mortar layer and spread until fully absorbed, followed by removal of excess material. Curing for approximately 12 hours is recommended before moving to the next step.
9.2.3 The epoxy colored sand self-leveling topping coat must be applied using self-leveling techniques to achieve a seamless finish.
9.2.4 The waterborne polyurethane topcoat shall be applied using a thin-coat roller method, ensuring even coverage and protection.
9.2.5 After construction, the floor must be cured strictly according to the product instructions. The flooring may only be put into service once the curing process is fully completed.
9.2.6 Upon completion, the finished flooring must be properly protected to prevent surface damage during handover or subsequent work.
10. Quality Inspection and Acceptance
10.1 General Provisions
10.1.1 At project acceptance, a re-inspection report of sampled materials upon delivery must be provided.
10.1.2 The quality inspection and acceptance of epoxy colored sand self-leveling flooring systems shall comply with the Code for Acceptance of Construction Quality of Building Ground Engineering (GB 50209).
10.1.3 All materials used, as well as indoor air quality after project completion, must comply with the Code for Indoor Environmental Pollution Control of Civil Building Engineering (GB 50325).
10.1.4 The quality inspection and acceptance batches for integrated flooring systems shall meet the following requirements:
- Each layer, construction section, or expansion joint shall constitute one inspection batch. For high-rise buildings, one batch may cover every three floors; if fewer than three, it shall still be counted as three.
- Each batch shall be randomly sampled by room or standard space, with not less than three samples. If fewer than three rooms exist, all shall be inspected. Corridors are counted as one room per 10 linear meters, while industrial workshops (by single span), auditoriums, or lobbies are counted as one room per two grid lines.
10.2 Key Control Items
For Epoxy Colored Sand Self-Leveling + Polyurethane Thin Topcoat:
- Appearance: Surface must be flat and smooth, free from cracks, color variations, pinholes, peeling, or missed areas. From 1 m vertical viewing distance, at least 90% of the surface must appear visually uniform.
- Surface Flatness (mm): ≤ 3, verified with a 2 m straightedge and wedge feeler gauge.
- Hollowing: For every 20 m² of flooring, no more than two hollow spots are allowed; each hollow must not exceed 400 cm², checked by tapping with a small hammer.
10.3 General Items
For Epoxy Colored Sand Self-Leveling:
- Slope: Must meet design requirements, verified by water test or slope gauge.
- Impact Resistance: No cracks or delamination. Test method: A 50 mm steel ball dropped freely from a height of 500 mm.
10.4 Acceptance Criteria
10.4.1 Acceptance of epoxy colored sand self-leveling flooring systems shall only proceed after inspection batches have passed quality tests and acceptance conditions are met.
10.4.2 A project shall be considered acceptable if it meets the following conditions:
- All inspection batches must be checked against both key control and general items.
- All key control items must pass.
- At least 80% of general inspection points must pass, and any failures must not affect usability.
- For projects with special requirements, additional tests may be conducted as per contract, including flatness, slip resistance, abrasion resistance, bond strength, stain resistance, chemical resistance, tensile strength, and hardness.
- Re-inspection reports of materials upon delivery must be provided.
- Construction plans and quality acceptance records must be complete.
- Records of concealed work inspections must be complete.
Appendix A – Explanation of Terminology Used in This Specification
To clarify the degree of strictness in the requirements of this standard, the following terms are defined:
- Absolute strictness – It must be done this way.
- Positive term: must
- Negative term: shall not
- Strictness under normal conditions – It shall be done this way.
- Positive term: shall
- Negative terms: should not or shall not
- Recommended option – When conditions allow, this is the preferred method.
- Positive term: should
- Negative term: should not
- Optional practice – Under certain conditions, this approach may be used.
- Term: may
When referring to compliance with other standards, the correct wording is: “shall comply with …” or “shall be carried out in accordance with …”.
Appendix B (Informative) – Drafting Organizations and Principal Drafters
This document was proposed and is under the jurisdiction of the Group Standard Committee of the Shandong Flooring Industry Association.
Drafting Organizations:
- Qingdao Xiuper Technology Co., Ltd.
- Grund (Qingdao) New Eco-friendly Building Materials Co., Ltd.
- Qingdao Mingfeng Building Materials Co., Ltd.
- Qingdao Haigude Trading Co., Ltd.
- Qingdao Pengfeng Building Materials Co., Ltd.
Principal Drafters: Zhang Gongmin, Gong Changjun, Xu Guodong, Ji Yujun, Sun Xianlin
Appendix C – References
[1] Floor Coating Materials GB/T 22374
[2] Code for Acceptance of Construction Quality of Building Ground Engineering GB 50209
[3] Code for Indoor Environmental Pollution Control of Civil Building Engineering GB 50325
[4] Technical Specification for Self-Leveling Flooring Engineering JGJ/T 175
