Airpop is the modern brand name for expanded polystyrene (EPS), a lightweight, closed-cell foam insulation material composed of approximately 98% air and 2% polystyrene. It is one of the most widely used insulation materials in the construction industry, valued for its excellent thermal performance, low weight, and versatility.
How it is made
EPS begins as small polystyrene beads containing a blowing agent (pentane). When heated with steam, the beads expand to many times their original size, filling with air. The expanded beads are then fused together in a mould under steam pressure, forming rigid blocks or custom shapes. The resulting material is extremely light yet structurally stable, with a density typically ranging from 15 to 35 kg/m3.
Application
Airpop (EPS) is used extensively in construction for insulation and structural purposes:
- Cavity wall insulation — EPS boards are fitted between the inner and outer leaves of cavity walls to reduce heat loss.
- Floor insulation — Placed beneath concrete floor slabs to prevent heat from escaping into the ground.
- Roof insulation — Used in flat and pitched roof constructions as a thermal barrier.
- External wall insulation (ETICS) — EPS boards form the insulating layer in external thermal insulation composite systems, finished with render.
- Lightweight fill — EPS blocks are used as lightweight fill material in road construction, embankments, and landscaping to reduce loads on underlying soil.
- Formwork — Permanent EPS formwork (ICF — Insulating Concrete Forms) serves as both mould and insulation for poured concrete walls.
Advantages
- Excellent thermal insulation — Low thermal conductivity (typically 0.031 to 0.038 W/mK)
- Lightweight — Easy to handle and transport, reducing labour costs
- Moisture resistant — Closed-cell structure absorbs very little water
- Recyclable — EPS can be mechanically recycled into new products
Related terms
- XPS (extruded polystyrene)
- Thermal insulation
- ETICS (External Thermal Insulation Composite System)
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