IS 10909:1984 is the Indian Standard (BIS) for expanded polystyrene (eps) for thermal insulation. This standard specifies the requirements, classification, sampling, and test methods for rigid expanded polystyrene (EPS) used as thermal insulation material. It classifies EPS into three types based on density (Normal, Heavy, Very Heavy Duty) and outlines mandatory physical properties such as thermal conductivity, compressive strength, and water absorption.
Specifies requirements for expanded polystyrene (EPS) products used for thermal insulation.
BIM-relevant code. See the BIM Hub for ISO 19650, IFC, and LOD/LOIN frameworks used alongside it.
| Parameter | IS Value | International | Source |
|---|---|---|---|
| Compressive Stress at 10% deformation (High Density Grade) | ≥ 1.5 kgf/cm² (approx. 147 kPa) | ≥ 150 kPa (for level CS(10)150) | EN 13163 |
| Thermal Conductivity (at 10°C mean temp, High Density) | ≤ 0.030 kcal/m.h.°C (approx. 0.035 W/m·K) | Declared value, typically ≤ 0.034 W/m·K for comparable density | EN 13163 |
| Water Absorption by full immersion (long term) | ≤ 2.0% by volume (for HD Grade) | ≤ 2% by volume (for level WL(T)2) | EN 13163 |
| Bending Strength (High Density Grade) | ≥ 2.5 kgf/cm² (approx. 245 kPa) | ≥ 250 kPa (for level BS250) | EN 13163 |
| Density (Normal Grade) | 15 - 22 kg/m³ | Nominal 21.6 kg/m³ (1.35 lb/ft³) for Type II | ASTM C578/C578M-23 |
| Dimensional Stability (Linear change at 70°C) | ≤ 1.5% (after 7 days) | ≤ 1% (for level DS(70,-)1, after 48 hours) | EN 13163 |