What is a PU/PIR insulated panel? Its build-up, advantages and use in modern construction

A close look at the build-up, the insulation principle and the advantages of PU/PIR panels — a material used widely in factories, cold stores, cleanrooms and industrial buildings.

Phú Sơn Group 27/07/2026 Insulated panels
What is a PU/PIR insulated panel? Its build-up, advantages and use in modern construction
Table of contents
  1. 1. What is a PU/PIR insulated panel?
  2. 2. How a PU/PIR panel is built up
  3. 3. Key advantages
  4. 4. In use on site
  5. 5. PU compared with PIR
  6. 6. Choosing and installing
  7. 7. Conclusion

1. What is a PU/PIR insulated panel?

A PU/PIR insulated panel is a sandwich panel built from a PU (polyurethane) or PIR (polyisocyanurate) insulation core between two skins of galvanized, pre-painted or stainless steel. It is produced on modern lines to a high dimensional accuracy, with outstanding thermal, acoustic and fire performance.

2. How a PU/PIR panel is built up

  • Steel facing: galvanized steel, aluminium-zinc coated steel or stainless steel, typically 0.35 – 0.7 mm thick.
  • Adhesive layer: a two-component polyurethane adhesive that bonds the steel to the core.
  • Insulation core: PU or PIR at 35 – 45 kg/m³ — high density and good insulating performance.
  • Interlocking joint: a tongue-and-groove or camlock joint that holds the panels tightly together and limits heat loss.
Profile drawing, PU/PIR interior wall panel - both faces plain - Phu Son GroupThe insulated panel line inside the Phu Son plantJavta PU/PIR interior wall panels made by Phu Son

Detailed build-up of the PU/PIR panel

3. Key advantages

Outstanding thermal insulation
A low thermal conductivity that holds temperatures steady.
Effective fire resistance
The PIR core resists flame spread well.
Fast installation
Light in weight with a solid interlock.
High durability
A 20–30 year service life, corrosion-resistant.
Good looking & flexible
A clean flat surface in a wide range of colors.

4. In use on site

With these advantages, PU/PIR panels are used widely across many sectors:

Industrial factory buildings
Industrial factory buildings
Cold storage – Storage warehouses
Cold storage – Storage warehouses
Cleanrooms and laboratories
Cleanrooms and laboratories
Food and pharmaceutical plants
Food and pharmaceutical plants

5. PU compared with PIR

Criterion PU (polyurethane) PIR (polyisocyanurate)
Thermal conductivity 0.022 – 0.024 W/m.K 0.019 – 0.022 W/m.K
Fire performance Moderate Very good
Thermal stability -40°C to +80°C -40°C to +120°C
Best suited to Factories, offices, civil buildings Cold stores, cleanrooms, projects with high fire requirements
Cost Lower Higher
Note: PIR resists fire and heat better than PU, which suits projects with demanding safety standards.

6. Choosing and installing

  • Match the panel thickness to how the building will be used and to the climate.
  • Favour a reputable manufacturer with quality certification and a clear warranty.
  • Install to procedure and seal the joints properly, so no heat escapes and no water gets in.
  • Maintain regularly and clean the steel surface to extend the building’s life.

Choosing the right panel and installing it properly lets a building perform at its best, cut running costs and stay safe for years.

– Phu Son Group

7. Conclusion

The PU/PIR insulated panel is a modern material that answers the demands of insulation, fire performance, fast installation and appearance. Picking the right panel and a reputable supplier gives a building better performance, lower cost and a longer life.

Need advice on the right solution for your project?

Phu Son Group's engineers are ready to help.

Advice on the right solution Fast, accurate quotations In-depth technical support
Request a consultation
Share this article: