IS 3348:1965 is the Indian Standard (BIS) for fibre insulation boards. This standard prescribes the requirements, dimensional tolerances, and test methods for fibre insulation boards manufactured from wood or other lignocellulosic materials, commonly used for thermal and acoustic insulation in buildings.
Specification for fibre insulation boards
| Parameter | IS Value | International | Source |
|---|---|---|---|
| Density | Not more than 400 kg/m³ | 160 to 280 kg/m³ (for Class 1, general purpose) | ASTM C208-12(2021) |
| Thermal Conductivity (k-value) | ≤ 0.05 kcal/m h °C (approx. 0.058 W/mK) at 20°C | Declared by manufacturer; typical values range from 0.038 to 0.060 W/mK at 10°C | EN 13171:2012+A1:2015 |
| Transverse Strength (Modulus of Rupture, for ~12mm board) | ≥ 10 kg/cm² (approx. 0.98 MPa) | ≥ 0.83 MPa (for boards < 14.3mm) | ASTM C208-12(2021) |
| Water Absorption (by volume, 2 hr immersion) | ≤ 10% (for 12mm thickness) | ≤ 10% (for regular sheathing grade) | ASTM C208-12(2021) |
| Tensile Strength (perpendicular to surface) | ≥ 0.7 kg/cm² (approx. 69 kPa) | Specified in levels, e.g., TR10 (≥10 kPa), TR20 (≥20 kPa), up to TR80 (≥80 kPa) | EN 13171:2012+A1:2015 |
| Thickness Tolerance | ±10% | Specified in classes, e.g., Class T3 is -3% to +5% | EN 13171:2012+A1:2015 |