Choosing the right pipes is crucial for your UFH system
When installing a water-based underfloor heating (UFH) system, choosing the right pipes is crucial for efficiency, durability, and ease of installation. The two most common options are:
- PERT (Polyethylene Raised Temperature) – Highly flexible, easy to install, and cost-effective, making it ideal for residential UFH.
- PEX (Cross-linked Polyethylene) – More rigid, highly durable, and suited for high-temperature or high-pressure applications.
While PEX is often chosen for plumbing and commercial heating, PERT is the better choice for most residential UFH systems due to its flexibility, lower cost, and ease of handling. This guide provides a balanced comparison of PERT vs PEX, focusing on durability, heat transfer, installation, and real-world performance.
🔗 Includes references to industry standards and expert sources
PERT vs PEX: Material Composition & Structure
What is PERT?
PERT (Polyethylene Raised Temperature Resistance) is a non-crosslinked polyethylene designed for temperature resistance and maximum flexibility.
✅ Easier to install due to superior flexibility
✅ More cost-effective than PEX
✅ Ideal for low-temperature heating systems like UFH
✅ Oxygen-barrier versions available for corrosion protection
❌ Lower pressure resistance than PEX
What is PEX?
PEX (Cross-linked Polyethylene) is a modified polyethylene that undergoes chemical cross-linking to improve durability and heat resistance.
✅ Higher pressure and temperature resistance than PERT
✅ Good for high-temperature plumbing and heating
❌ Less flexible, making installation harder
❌ Requires special tools for shaping and connecting
🔗 PEX Pipe Overview – Instantor UK
Comparisons:
Oxygen Barrier & Corrosion Resistance
Oxygen entering a UFH system can cause corrosion in metal components like manifolds and boilers. Some pipes include an oxygen barrier to prevent this.
| Pipe Type | Oxygen Barrier? | Corrosion Resistance |
|---|---|---|
| PERT (Non-barrier) | ❌ No | ✅ Yes (Plastic-based) |
| PERT (Barrier – EVOH) | ✅ Yes | ✅ Yes |
| PEX (Non-barrier) | ❌ No | ✅ Yes (Plastic-based) |
| PEX (Barrier – EVOH) | ✅ Yes | ✅ Yes |
🔹 PERT with an EVOH barrier offers the same oxygen protection as PEX but with easier installation.
🔗 Importance of Oxygen Barriers in UFH Pipes – UFH Express
Heat Transfer Efficiency & Thermal Conductivity
Both PERT and PEX transfer heat efficiently, but PERT has a slight advantage.
| Pipe Type | Thermal Conductivity (W/m·K) |
|---|---|
| PERT | 0.40 ✅ (Slightly better) |
| PEX | 0.38 |
🔹 PERT’s better heat conductivity means slightly faster heat-up times in UFH applications. However, in a well-designed UFH system, the difference is minor.
🔗 Comparison of PEX & PERT for Heating – The UFH Group
PERT is Easier to Install Than PEX
| Pipe Type | Flexibility | Installation Ease |
|---|---|---|
| PERT | ✅ Very flexible | ✅ Easy to install |
| PEX | ❌ Less flexible | ❌ Requires tools |
🔹 PERT is significantly easier to handle, bend, and fit, making it ideal for fast, cost-effective UFH installations.
🔗 Installation Guide for UFH Pipes – Plumber Grays
Longevity & Durability: PERT vs PEX in UFH
PEX is more temperature and pressure resistant, but for UFH, PERT is more than sufficient.
| Pipe Type | Max Temp (°C) | Max Pressure (bar) | Lifespan |
|---|---|---|---|
| PERT | 70°C ✅ (Perfect for UFH) | 6 bar | 50+ years |
| PEX | 95°C | 10 bar | 50+ years |
🔹 Since UFH systems operate at 30-50°C, both PERT and PEX are equally durable in this application.
🔗 PEX vs PERT Temperature Ratings – Lesso UK
PERT is the Best Choice for Residential UFH
| Feature | PERT | PEX |
|---|---|---|
| Flexibility | ✅ Very flexible | ❌ Less flexible |
| Ease of Installation | ✅ Easier to install | ❌ Requires tools |
| Heat Transfer | ✅ Slightly better | 🔹 Slightly lower |
| Corrosion Resistance | ✅ Yes | ✅ Yes |
| Best for Screed UFH? | ✅ Yes | ✅ Yes |
| Best for Dry UFH? | ✅ Yes | ❌ Less suitable |
| Price | 💰 Lower cost | 💰💰 Higher cost |
✔ Why PERT is the Best Choice for Residential UFH
- More flexible & easier to install than PEX.
- Transfers heat slightly better, improving efficiency.
- Lower cost, making it ideal for affordable home heating solutions.
- No special tools needed, saving time & installation effort.
- More than sufficient for UFH operating temperatures and pressures.
🔗 Shop PERT Pipes for UFH – The UFH Group
Final Verdict: Choose PERT for Residential UFH
If you are installing underfloor heating in a home, PERT is the best choice because:
✅ More flexible and easier to install than PEX.
✅ No need for extra tools – simple push-fit connections.
✅ Transfers heat slightly better, improving efficiency.
✅ Lower cost than PEX, making it budget-friendly for homeowners.
✅ Sufficient temperature and pressure ratings for UFH systems.
🔹 PEX remains a strong option for commercial or high-pressure heating, but for residential UFH, PERT is the smarter, more cost-effective choice.
🔗 Learn More About PERT UFH Pipes – UFH Direct
What’s Your Experience? Let Us Know! 🚀
💬 Comment below with your thoughts on PERT vs PEX for UFH!
For Free advice from our Experts, Contact UFH Direct here
References & Industry Sources
🔗 Water Regulations Advisory Scheme (WRAS) – Dezincification in Plumbing Systems
🔗 Energy Saving Trust (UK) – https://energysavingtrust.org.uk
🔗 UFH Direct (Industry Experts in Underfloor Heating Piping) – https://www.ufhdirect.co.uk
