PE-RT 5-LAYER OXYGEN BARRIER-PIPE
Legom PE-RTII Type Pipe is a second-generation raised temperature resistant polyethylene pipe engineered for underfloor heating, hydronic HVAC, and domestic hot water systems. The Type II designation indicates a higher-grade PE-RT material with improved long-term hydrostatic strength and creep resistance compared to standard PE-RT Type I, enabling use at higher pressures and temperatures without requiring cross-linking. With a Vicat softening temperature above 130°C and an oxygen permeability of ≤0.32 mg/m²d per DIN 4726, the PE-RTII pipe is built for demanding thermal cycling applications where long-term dimensional stability and corrosion protection are priorities.
Unlike PEX pipe, PE-RTII achieves its elevated temperature performance through controlled crystalline molecular structure during manufacturing rather than a post-extrusion cross-linking process. This allows the pipe to be joined using standard heat-fusion (hot-melt) methods, simplifying field connections and enabling repairs without specialized tooling. The smooth inner bore with a roughness coefficient of 0.0015mm minimizes flow resistance and scale accumulation over the pipe’s service life.
Key Benefits
- PE-RT Type II material grade – Higher long-term hydrostatic strength than Type I, allowing use at elevated pressures and temperatures that Type I cannot reliably sustain over the pipe’s design service life
- Vicat softening temperature above 130°C – Maintains structural integrity at temperatures significantly above normal underfloor heating operating range, providing a wide safety margin against heat deformation
- Oxygen barrier protection – Oxygen permeability of ≤0.32 mg/m²d at 40°C per DIN 4726 limits oxygen ingress into the heating circuit, protecting metal system components from corrosion-induced failure
- Hot-melt (heat-fusion) connection compatible – Unlike PEX, PE-RTII can be joined using standard butt fusion, socket fusion, or electrofusion methods, enabling field connections and repairs without specialist tools or fittings
- Enhanced flexibility for easier installation – The pipe’s inherent pliability allows it to be bent and routed through floor heating loop patterns without becoming brittle, reducing the number of fittings required
- Low-temperature impact resistance – Impact strength of 20 KJ/m² at 0°C per ISO 868 confirms the pipe remains tough and resistant to cracking during cold-weather installation and in low-ambient-temperature service environments
- Smooth bore for efficient flow – Roughness coefficient of 0.0015mm minimizes hydraulic resistance and reduces the risk of scale and biofilm accumulation over the pipe’s service life
- Corrosion and scale resistant – Immune to electrochemical corrosion that affects copper and steel pipe, and resistant to the mineral scale buildup common in hard water areas
- OEM and ODM customization available – Pipe diameter, coil length, wall thickness, and labeling can be customized for distributor and system integrator requirements
Technical Specifications
| Product Parameter | Unit | Standard Value | Standard |
|---|---|---|---|
| Density | g/cm³ | 0.947 | ISO 1183 |
| Tensile yield stress [20°C] | MPa | > 23 | ISO 527 |
| Tensile yield elongation [20°C] | % | > 350 | ISO 6259 |
| Elastic modulus | MPa | 750 | ISO 178 |
| Impact strength [0°C] | KJ/m² | 20 | ISO 868 |
| Thermal expansion coefficient [20°C] | m/m°K | 18E-4 | DIN 53752 |
| Thermal conductivity [60°C] | W/m°K | 0.42 | DIN 52612 |
| Vicat softening temperature | °C | > 130 | ISO 2507 |
| Oxygen permeability [40°C] | mg/m²d | ≤ 0.32 | DIN 4726 |
| Roughness coefficient | mm | 0.0015 | acc. to Prandtl-Colebrook |
Application & Use Cases
- Underfloor heating systems – Flexible enough to follow serpentine and spiral loop patterns in wet screed or dry panel systems, with oxygen barrier protection for the hydronic circuit
- Domestic hot water systems – The higher Type II material grade supports sustained hot water delivery temperatures, and the heat-fusion joining method provides reliable, leak-free connections in potable water circuits
- Hydronic HVAC distribution – Suitable for low and medium-temperature hot water distribution in heating systems connected to heat pumps, condensing boilers, or district heating networks
- Radiant ceiling and wall heating – The pipe’s flexibility and smooth bore suit radiant panel systems where tight bends and low-resistance flow are design requirements
- Cold-climate installations – Impact strength of 20 KJ/m² at 0°C confirms the pipe can be installed and handled in winter conditions without cracking or becoming brittle
- Renovation and retrofit projects – The heat-fusion joining method enables field connections and mid-run repairs without dedicated expansion tooling, reducing repair complexity in finished floor installations
Installation Notes
- Store pipe coils in a cool, shaded location away from direct sunlight and heat sources before installation to prevent premature deformation
- Maintain the minimum bend radius specified for the pipe diameter. Forcing the pipe below minimum bend radius causes kinking that permanently restricts flow
- PE-RTII pipe can be joined using heat-fusion methods including socket fusion, butt fusion, and electrofusion. Use fittings and tools rated for PE-RT Type II material. Do not use PEX-specific expansion or crimp fittings
- Use pipe staples, clips, or rail systems at recommended spacing intervals to hold the pipe in position before screed or concrete is poured in wet system installations
- In dry system installations with aluminum diffuser plates, ensure the pipe seats fully into the plate channel for maximum thermal contact
- Allow adequate expansion clearance at pipe entry and exit points through walls and floor edges. The thermal expansion coefficient of 18E-4 m/m°K is higher than PEX — account for greater expansion in long straight runs
- Conduct a pressure test before screed or concrete is poured. Test at a minimum of 1.5 times the intended working pressure for at least 30 minutes
- Label each loop at the manifold connection point during installation to simplify commissioning and future maintenance
Frequently Asked Questions
What is the difference between PE-RT Type I and PE-RT Type II?
Both Type I and Type II are raised temperature resistant polyethylene pipes that achieve their thermal performance through controlled crystalline structure rather than cross-linking. The key difference is long-term hydrostatic strength. PE-RT Type II has superior resistance to creep and sustained stress at elevated temperatures, making it suitable for higher design pressures and temperatures over the pipe’s rated service life. Type II also qualifies for use in single-layer pipe constructions in more demanding applications where Type I requires a multilayer design. For underfloor heating at standard design conditions, both types perform well; Type II provides greater engineering margin for higher-temperature or higher-pressure systems.
How does PE-RTII compare to PEX pipe for underfloor heating?
PE-RTII and PEX are both widely used for underfloor heating. The primary practical difference is in how they are joined. PE-RTII can be joined using standard heat-fusion methods (socket fusion, butt fusion, electrofusion) — the same techniques used for standard polyethylene pipe — making field connections and repairs straightforward. PEX requires specialized expansion, crimp, or press fittings and cannot be heat-fused. PEX typically has higher long-term creep resistance due to cross-linking, while PE-RTII Type II provides comparable performance through its superior molecular structure. See also: PEX Type Pipe.
Why is the oxygen barrier important?
Oxygen permeating through the pipe wall into the heating water circuit causes oxidation of metal components — pumps, boiler heat exchangers, and manifold valves — producing sludge and accelerating corrosion-related failure. The PE-RTII pipe’s oxygen permeability of ≤0.32 mg/m²d at 40°C per DIN 4726 limits this ingress to a level that protects system components and extends their service life considerably compared to unprotected pipe.
What does the roughness coefficient of 0.0015mm mean in practice?
The roughness coefficient determines how much resistance the inner pipe wall creates against water flow. A lower roughness value means less turbulence and lower pressure drop per metre of pipe length. At 0.0015mm, the PE-RTII inner bore is extremely smooth, which reduces pump energy consumption, minimizes the risk of scale and biofilm attaching to the pipe wall, and maintains consistent flow rates throughout the system’s service life.
What sizes and coil lengths are available?
Please contact the Legom team for current availability of pipe diameters, wall thicknesses, and coil lengths. OEM and ODM orders can be fulfilled with custom specifications including diameter, wall thickness, coil length, and print labeling.
Can Legom PE-RTII pipe be customized for private label or OEM supply?
Yes. Legom supports full OEM and ODM services for PE-RTII Type Pipe including custom dimensions, coil lengths, color, and branded printing on the pipe surface. All customization projects are handled under strict confidentiality. Contact our team to discuss your requirements.
OEM & ODM Customization
Legom supports full OEM and ODM services for PE-RTII Type Pipe. Our manufacturing team can customize pipe diameter, wall thickness, coil length, surface printing, and packaging to match your product and brand requirements. All customization projects are handled with strict confidentiality. Contact us via WhatsApp or info@legomsmart.com.
Product information last reviewed by the Legom Technical Team. For the most current specifications, refer to the official datasheet or contact our sales team.
Related products
Custom OEM & ODM Solutions
Legom is a direct manufacturer offering end-to-end OEM and ODM services. With our in-house engineering and production capabilities, we work closely with distributors and system integrators to deliver fully customized solutions under strict NDA.
