Use Case
When building a cool room, freezer, or pharmaceutical clean room in Australia, the most critical decision you will make is choosing the right insulation core. The two industry standards are EPS (Expanded Polystyrene) and PIR (Polyisocyanurate) sandwich panels.
While they may look identical from the outside with their steel skins, their performance in a fire, their thermal efficiency, and their price points are vastly different. In this guide, we break down the pros and cons of each to help you make an informed decision for your project.
1. What is EPS Sandwich Panelling?
EPS (Expanded Polystyrene) is the traditional standard for cold storage insulation. It is a lightweight, rigid plastic foam material produced from solid beads of polystyrene.
Key Characteristics of EPS:
- Composition: 98% air trapped within a closed-cell structure.
- Cost: Generally more affordable than PIR.
- Common Uses: General dry goods storage, standard cool rooms, and budget-conscious construction projects.
EPS is an excellent insulator against heat and sound. It is lightweight, making it easy to handle during installation. However, its thermal resistance (R-value) is lower than PIR, meaning you often need thicker panels to achieve the same insulation result.
2. What is PIR Sandwich Panelling?
PIR (Polyisocyanurate) is the next generation of insulation. It is a thermoset plastic produced as a foam and used as a rigid thermal insulation. It significantly outperforms EPS in thermal efficiency and fire resistance.
Key Characteristics of PIR:
- Composition: A complex chemical structure that chars rather than melts when exposed to fire.
- Thermal Efficiency: Superior insulation per millimetre of thickness.
- Common Uses: Freezers, high-risk fire zones, insurance-driven projects, and high-efficiency buildings.
3. The Big Comparison: EPS vs. PIR
To help you decide, we’ve compared the two materials across the factors that matter most to Australian business owners: Insulation, Fire Safety, and Cost.
| Feature | EPS (Expanded Polystyrene) | PIR (Polyisocyanurate) |
|---|---|---|
| Thermal Conductivity (K-Value) | ~0.038 W/mK (Good) | ~0.022 W/mK (Excellent) |
| Fire Behaviour | Can melt and contribute to fire spread. | Self-extinguishing; chars instead of melting. |
| Moisture Resistance | Moderate. | High (Closed-cell structure). |
| Cost | Lower initial investment. | Higher investment, but lower energy bills. |
| Panel Thickness Required | Thicker (e.g., 100mm) | Thinner (e.g., 75mm) for same result. |
4. Why Fire Safety Matters in Australia
The most significant difference between EPS and PIR is their reaction to fire. In Australia, compliance with the National Construction Code (NCC) is strict.
PIR panels are often required for insurance approval because they do not promote the spread of flame. When exposed to fire, PIR forms a stable char layer that protects the inner core, preventing the rapid spread of fire. Conversely, untreated EPS can melt and potentially act as fuel for a fire.
Tip: If your cool room is located near a boundary line or inside a high-occupancy building, we almost always recommend PIR panels to meet Australian Standards.
5. Which Panel Should You Choose?
Choose EPS Panels If:
- You are working with a tight construction budget.
- The facility stores low-value goods with low fire risk.
- You have ample space and don’t mind using thicker walls to achieve insulation goals.
Choose PIR Panels If:
- Energy efficiency is a priority: You want to lower your monthly electricity bills.
- Space is limited: You need thinner walls to maximise internal storage space.
- Insurance requirements: Your insurer mandates fire-resistant materials.
- Freezer applications: You require superior thermal performance for sub-zero temperatures.
Conclusion
Both EPS and PIR sandwich panels have their place in the Australian market. EPS offers a cost-effective solution for standard projects, while PIR delivers superior safety, thermal performance, and longevity.
At Cool Room Masters, we supply and install both options tailored to your specific needs.
Need help selecting the right panel for your project?
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