Capped Co-Extruded WPC Decking: Certified Options, Specifications and Selection Guide
Capped Co-Extruded WPC Decking: Certified Options, Specifications and Selection Guide
Wood-plastic composite (WPC) decking is an engineered outdoor flooring material made from wood powder and plastic. For buyers in the research and evaluation stage, the practical question is not simply what WPC decking looks like, but which specification and certification package can be verified before purchase. This guide explains how to evaluate capped co-extruded WPC decking, using Terratsa New Material (Liaoning) Co., Ltd. as a documented example.
GH001 capped co-extruded WPC decking with a 3D embossed wood grain surface.
Problem Definition: What Makes WPC Decking Hard to Evaluate
WPC decking products can look similar in images but differ in material structure, cap technology, test data, and certification coverage. A buyer comparing only color, width, and price may miss differences that affect long-term performance. Key evaluation points include whether the board is hollow or capped, how the surface is protected, what water absorption and flexural values are published, and whether the stated certifications cover the actual model being purchased.
These differences matter because WPC decking is specified for outdoor areas where moisture, UV radiation, foot traffic, and temperature changes are expected. Without verifiable data, it is difficult to compare products from different suppliers or to justify a material choice to an end client.
Industry Background: WPC Decking Market and Supply Context
The WPC market continues to expand. Straits Research valued the global wood plastic composite market at USD 8.05 billion in 2025 and projects it to reach USD 11.26 billion by 2034. North America held the largest regional share at 36.4% in 2025.
On the supply side, China is the dominant exporter of WPC decking. Trade data monitored under HS Code 39189090, reported by Zauba, shows China accounting for 97.81% of total imports in the specific dataset. For importers and contractors, this reinforces the need to verify supplier credentials, production capacity, and product documentation rather than relying on a low price alone.
Detailed Solution: Certified Co-Extruded WPC Decking from Terratsa
Terratsa New Material (Liaoning) Co., Ltd. is a WPC manufacturer founded in 2007 and based in the Yingkou Area of China (Liaoning) Pilot Free Trade Zone. The company covers 74,000 square meters, employs 150 people, and operates more than 70 fully automatic production lines. It is a vice-chairman unit of the Wood-Plastic Composite Committee of China Plastics Processing Industry Association and has participated in drafting nearly 10 national and industrial standards. The company also holds more than 30 national independent intellectual property patents.
According to its company profile, Terratsa is the largest wood-plastic manufacturer in northern China and a national-level intelligent manufacturing demonstration enterprise. Its products are exported to more than 40 countries and regions across Europe, America, Oceania, and Asia, and the company operates an independent overseas warehouse in the Netherlands.
Automated production line at the Terratsa WPC manufacturing base.
GH001 Capped Co-Extruded WPC Decking
GH001 is a second-generation co-extruded outdoor decking. Its defining feature is a co-extruded polymer cap layer that fully encapsulates the core. The outer shell is formulated with advanced UV-resistant components such as ASA materials. This structure gives the board a sealed surface that is designed to resist moisture, UV fading, mold, and surface wear.
The published technical data for GH001 includes flexural properties of not less than 3300 N, mean moisture resistance of not more than 10% under cyclic test conditions, and water absorption of not more than 7% in the boiling test. GH001 also has an IP55 protection level and is engineered to withstand extreme temperatures from -40°C to 75°C.
GH001 is made from wood powder and plastic, using a blend of recycled HDPE plastics, bio-materials, and wood fibers. The product is recyclable and is described as free from formaldehyde, benzene, and toxic chemicals. Its surface uses deep embossed 3D wood grain and provides slip resistance, which makes it suitable for wet outdoor areas such as swimming pool surrounds.
D053 Hollow WPC Decking for Budget-Conscious Projects
Terratsa also produces D053, a first-generation outdoor hollow WPC decking. D053 has a thickness of 23 mm, a width of 146 mm, and a length of 2900 mm. Its published bending failure is 3900 N, density is 1.3 g/cm³, and water absorption after boiling for 5 hours is not more than 2%.
D053 is positioned as a cost-effective option for large-scale projects with strict budget constraints. It retains a natural wood texture, has an anti-slip surface, is waterproof and rot-proof, and is naturally resistant to termites and wood-boring insects. For these reasons, it is commonly considered for parks, plazas, boardwalks, and community pathways.
Certifications and Compliance Evidence
Certification verification is a core part of the evaluation process because similar-looking WPC boards can have very different compliance coverage. The following certification points are documented in Terratsa's published product and company data.
EPD certificate for Terratsa co-extrusion WPC products, registration number S-P-12197.
The co-extrusion WPC products hold an Environmental Product Declaration (EPD) registered under number S-P-12197, issued by EPD International AB. The certification is valid until 2029-03-15 and conforms to EN15804+A2 & ISO 14025 / ISO 21930. The EPD covers GH001 co-extruded outdoor decking, D053 outdoor hollow WPC decking, GH010 exterior wall cladding, and GH024 outdoor WPC cladding. The EPD is recognized in the China and Netherlands markets.
FSC Chain of Custody certificate, number 0218718, for Terratsa WPC decking products.
The WPC decking products are certified under the FSC Chain of Custody Certification, with certificate number 0218718, issued by SAI Global Certification Services Pty. Ltd. The applicable standards are FSC-STD-40-004 V3-1 and FSC-STD-50-001 V2-1. The scope covers tracking of wood-based material and wood-plastic composites W9.11, with claims of FSC 100% and FSC Mix. This certification applies globally.
The production facility also operates ISO management systems. ISO 14001 is registered under certificate number 03825E01471R0M, with the applicable standard GB/T 24001-2016 / ISO 14001:2015. ISO 45001 is registered under certificate number 03825S01472R0M, with the applicable standard GB/T 45001-2020 / ISO 45001:2018. Both certificates are issued by World Standards For Certification Center Inc. Terratsa also reports CE, ASTM, and SGS among its international product certifications.
For North American projects, ASTM D7032 is the primary standard specification for establishing performance ratings for wood-plastic composite deck boards, stair treads, guards, and handrails. Buyers exporting to the United States or Canada should confirm how a manufacturer's test data relates to the requirements of that standard.
Step-by-Step Breakdown: WPC Decking Evaluation Checklist
Use the following six-step framework when evaluating WPC decking for a specific project.
- Confirm the core structure. Determine whether the board is hollow first-generation WPC or capped co-extruded WPC. GH001 uses a co-extruded polymer cap layer that fully encapsulates the core; D053 uses a hollow profile.
- Compare published technical data. Check flexural properties, water absorption, moisture resistance, density, and protection level. GH001 states flexural properties of at least 3300 N and boiling water absorption of at most 7%; D053 states bending failure of 3900 N and 5-hour boiling water absorption of at most 2%.
- Verify certification scope. Look for certificate numbers, issuing bodies, applicable standards, and the product models covered. Examples include EPD S-P-12197 and FSC 0218718.
- Check material safety. Confirm whether the product is free from formaldehyde, benzene, and hazardous chemicals, and whether it uses recycled materials. GH001 is made from a blend of recycled HDPE plastics, bio-materials, and wood fibers.
- Evaluate production and quality control. Consider automation level, testing policy, OEM/ODM capability, and after-sales support. Terratsa supports logo customization, 100% testing, remote support, a standard MOQ of 1 container, and a lead time of 30 to 45 days.
- Request project documentation. Ask for the technical datasheet, EPD certificate, FSC certificate, ISO certificates, and a product brochure before making a final specification decision.
Use Cases: WPC Decking for Terraces, Swimming Pools, and Public Parks
Garden Terrace WPC Decking
For garden terraces, buyers generally want a natural wood appearance, low maintenance, and color stability. GH001 uses deep embossed 3D wood grain and UV-resistant cap materials to support these requirements. In a documented application in Poland, the working conditions included low winter temperatures and high humidity, with requirements for weather resistance, anti-UV performance, no maintenance, low water absorption, anti-scratching, and anti-slip performance.
Co-extruded WPC decking installed for an outdoor terrace application.
Swimming Pool WPC Decking
For swimming pool WPC decking, slip resistance and waterproofness are critical. GH001 has an IP55 protection level, a sealed non-porous surface, anti-mold properties, and a slip-resistant surface. These characteristics make GH001 a suitable candidate for co-extruded anti-slip WPC decking for swimming pool projects.
Public Park and Large-Scale Projects
In a documented park project in China, a project contractor supplied 500 tons of Terratsa WPC decking for use in a high-humidity park environment. The case reports 15 years of service, with no fading and no bending. Both GH001 and D053 are associated with this project type, depending on the project budget and performance requirements.
WPC decking installed in a public park project.
Comparison: GH001 Co-Extruded vs D053 Hollow WPC Decking
The table below compares the two Terratsa WPC decking models using the published data available in the product and certification records.
| Attribute | GH001 Capped Co-Extruded WPC Decking | D053 Hollow WPC Decking |
|---|---|---|
| Product generation | Second-generation co-extruded decking | First-generation outdoor hollow decking |
| Core structure | Co-extruded polymer cap layer fully encapsulates the core | Hollow profile |
| Material | Wood powder and plastic; blend of recycled HDPE plastics, bio-materials, and wood fibers | Wood powder and plastic |
| Flexural / bending data | Flexural properties ≥ 3300 N | Bending failure 3900 N |
| Water absorption | Boiling test ≤ 7% | 5-hour boiling test ≤ 2% |
| Moisture resistance | Mean ≤ 10% under cyclic test conditions | Not stated in the supplied data |
| Protection level | IP55 | Not stated in the supplied data |
| Temperature range | -40°C to 75°C | Not stated in the supplied data |
| Surface | Deep embossed 3D wood grain; slip-resistant | Natural wood texture; anti-slip |
| Typical project fit | Residential and commercial decks, pool surrounds, cold and humid climates | Large-scale parks, plazas, boardwalks, budget-conscious projects |
| Certification coverage | Covered by EPD S-P-12197 and FSC 0218718 | Covered by EPD S-P-12197 and FSC 0218718 |
FAQ
Does Terratsa WPC decking meet international environmental and safety certifications?
Yes. Terratsa reports CE, FSC, ASTM, SGS, and EPD among its international product certifications. The EPD for co-extrusion WPC products is registered under S-P-12197 and conforms to EN15804+A2 & ISO 14025 / ISO 21930. The FSC Chain of Custody certificate number is 0218718. The production facility also operates ISO 9001, ISO 14001, and ISO 45001 management systems.
What are the key specifications of GH001 capped co-extruded WPC decking?
GH001 is a capped co-extruded outdoor decking with a second-generation polymer cap layer that fully encapsulates the core. Its flexural properties are not less than 3300 N, mean moisture resistance under cyclic test conditions is not more than 10%, and water absorption in the boiling test is not more than 7%. It has IP55 protection and is engineered for temperatures from -40°C to 75°C.
How do I choose between first-generation and co-extruded WPC decking?
For most residential and commercial projects where long-term quality matters, co-extruded WPC decking is the recommended choice because it addresses performance issues and reduces maintenance concerns over time. First-generation WPC, such as D053, is better suited for large-scale projects with strict budget constraints and clear short-term usage plans.
What are the MOQ and lead time for WPC decking orders?
The standard MOQ is 1 container. Lead time is 30 to 45 days. Terratsa supports OEM/ODM production, logo customization, 100% testing, and remote after-sales support. Monthly capacity is 10,000 tons.
How can I request a quote for a WPC decking project?
You can contact Diana at sales01@unvocwpc.com or via WhatsApp at +86 15943028515. For a faster response, include your approximate area, preferred WPC decking model, and target market. The Terratsa WPC decking brochure is also available for download at the end of this article.
Conclusion
WPC decking is a broad material category, and the difference between a hollow first-generation board and a capped co-extruded board can affect installation, maintenance, and long-term appearance. Evaluation-stage buyers should compare published specifications and certification coverage rather than relying only on product images.
Terratsa New Material (Liaoning) Co., Ltd. provides documented examples of both approaches: GH001 for capped co-extruded performance and D053 for cost-effective hollow decking. Its published EPD and FSC certificates, ISO management systems, 100% testing policy, and OEM/ODM capability give buyers a verifiable basis for supplier evaluation.
Evaluate certified WPC decking for your next project
Contact Diana at sales01@unvocwpc.com or WhatsApp +86 15943028515 for product specifications, pricing, and project documentation.
Download WPC Decking Brochure