Types of Insulator Materials

The energy efficiency of a building often depends on the materials used to create its envelope. A project's compliance with today's increasingly stringent energy standards depends to a large extent on the type of insulation used. PIR, PUR, XPS and EPS are popular insulation materials, each with its own specific qualities. This article outlines the differences between these products to enable you to choose the best type of insulation for your project.

Manufacturing processes differ

1. What is XPS?

XPS (extruded polystyrene insulation) is manufactured using extrusion: a continuous process that creates a closed-cell structure with smooth skin on the top and bottom of the board. the closed-cell structure of XPS prevents water from penetrating the structure of the insulation board and provides long-term strength and durability.

Foil-Clad XPS      

2. What is EPS?

EPS (Expanded Polystyrene Insulation) is manufactured using foam beads in a mould. Heat or steam is applied directly to the beads, causing them to expand and fuse together. A cubic metre of EPS contains approximately 10 million beads, each with approximately 3000 closed and air-filled cells. In other words, EPS consists of 2% polystyrene and 98% air. The manufacturing process produces a closed-cell structure, but not a closed-cell insulating board (due to the possibility of voids between the beads).

3. PIR and PUR

PIR and PUR are closed-cell insulating materials, like XPS, but in contrast to EPS and XPS, the main components of PIR and PUR are chemicals. The latter insulation products consist of a foam inserted between two linings or finishes, such as multi-layer aluminium finishes or mineral wool. On the one hand, these finishes ensure that the foam stays in place. On the other hand, the gases they trap are the reason for the excellent lambda values of the PU product range.

What is the difference between XPS and EPS foam?

• Extruded Polystyrene - Insulation Extruded Polystyrene (XPS) is also a thermoplastic polymer. XPS has a closed-cell structure, is generally stronger, has higher mechanical properties and is generally more expensive than EPS in principle. XPS is produced from the same base material as EPS and is therefore also based on crude oil. The production process of XPS differs only slightly from that of EPS.

Similar to EPS, XPS has a wide range of applications. It can be used for the insulation of buildings, roofs and concrete floors. XPS materials can also be used for crafts and modelling, especially for architectural models.

 XPS Panel

Although both expanded polystyrene and extruded polystyrene have a closed-cell structure, they can be permeated by water molecules and cannot be considered as a vapour barrier. In expanded polystyrene, there are gaps between the expanded closed-cell particles and these gaps form a network of open channels between the bonded particles. If water freezes, it expands and causes the polystyrene particles to fall out of the foam.

Applications: What is the difference between PIR and XPS?

The best choice of insulation material depends on the individual engineering situation.

XPS has many applications.

Particularly suitable for inverted roofs due to its closed-cell structure and extreme resistance to moisture.

Due to its excellent compressive strength, it is often used in floor slabs, concrete floors, foundations and underground work.

PIR and PUR

They cannot be used for inverted roofs, but are compatible with conventional warm roofs.

Whether you need more information, samples, or a quote, we would be delighted to talk to you.