Overview
ISO 29769:2008 - Thermal insulating products for building applications - Determination of behaviour under point load - specifies a laboratory test method for assessing how thermal insulation products respond when a concentrated (point) force is applied. The standard is intended to verify whether insulating materials have sufficient local strength to resist loads encountered during installation or in service (for example pedestrian traffic over floor insulation).
Keywords: ISO 29769:2008, thermal insulating products, point load test, behaviour under point load, force-deformation curve.
Key topics and requirements
- Scope: Applies to thermal insulating products and defines equipment, specimen preparation, conditioning, procedure, calculation and reporting.
- Test principle: A circular steel indenter applies a compressive point load at constant speed to a square specimen while recording force-displacement (force-deformation) data to determine the critical point and/or force at a specified deformation.
- Apparatus:
- Compression testing machine with a rigid plate and indenter.
- Cylindrical indenter: 79.8 ± 0.1 mm diameter (circular cross-section).
- Continuous displacement and force measurement and recording devices (displacement reading to ±5% or ±0.1 mm; force to ±1%).
- Specimens:
- Typical size 300 mm × 300 mm, retaining original thickness, skins/facings/coatings kept unless otherwise noted.
- At least 3 specimens if not otherwise specified.
- Dimensional checks per ISO 29768.
- Procedure:
- Preload (2.5 ± 0.25) N (≈500 ± 50 Pa).
- Indenter speed (50 ± 5) mm/min.
- Stop when a critical point is identified or deformation reaches 20%; optionally record force at 5 mm deformation.
- Conditioning & environment:
- Standard: (23 ± 5) °C (dispute condition 23 ± 2 °C, 50 ± 5% RH).
- Tropical alternative: 27 °C, 65% RH (if applicable, must be reported).
- Accuracy:
- Estimated 95% repeatability limits: ~5% (load at fixed deformation) and ~8% (point load strength).
- Estimated 95% reproducibility limits: ~15% and ~25%, respectively.
- Reporting: Must include reference to ISO 29769, product ID, conditioning, deviations, test data and environmental conditions.
Applications and users
- Product manufacturers validating local compressive strength of insulating boards, panels or under-screed layers.
- Test laboratories performing certification, quality control and comparative testing.
- Specifiers, architects and contractors assessing suitability of insulation for areas exposed to concentrated loads (installation traffic, maintenance access, floating floors).
- Regulatory bodies and standards writers referencing a harmonized method for point-load performance.
Related standards