The short answer
Both PU and PIR are rigid polyurethane foam sandwich panels with excellent insulation. The difference is in how the foam reacts to fire. For most chilled cold rooms PU is perfectly adequate; for freezers, high-risk or insurance-sensitive facilities, PIR is the safer choice.
What they have in common
- Thermal conductivity around ≤ 0.023 W/m·K
- Density of about 40 kg/m³
- The same camlock joint systems and thickness range (30–200 mm)
- Compatible with the same cold room doors and installation materials
Where they differ
PIR (polyisocyanurate) has a modified molecular structure that forms a char layer when exposed to flame, which slows fire spread and gives a higher oxygen index. It typically meets B1 fire class and is the usual choice for cold storage where fire performance matters.
PU (polyurethane) is the classic cold room core. Slightly lower cost, excellent insulation, and still B1-rated in most cold room grades — but less forgiving at very high temperatures.
How to choose
- Chilled rooms (0 to +8°C), food processing, logistics: PU is usually fine and cost-effective.
- Freezers (–18 to –25°C), high-bay warehouses, tall buildings: choose PIR.
- Fire-rated walls or insurance requirements: choose PIR, or go further and use rockwool (A2).
Not sure which fits your project? Send us your drawings and temperature range — we will recommend the correct core and thickness.
Need a quote for your cold room project? Our production base in Changzhou, China supplies PIR/PU panels, rockwool panels, cold room doors, installation materials and equipment. Founded 2013 · 50,000 m² production base · 80,000 m² monthly capacity · 5–7 day delivery · MOQ 500 m².