Overview
ISO 16534:2020 - Thermal insulating products for building applications - Determination of compressive creep - specifies the equipment and laboratory test method for measuring the compressive creep of thermal insulating products under sustained compressive stress. The standard defines the test principle, required apparatus, specimen preparation and conditioning, test procedure, calculation and reporting requirements. It is the second edition (2020) and replaces the earlier edition.
Key topics and technical requirements
- Scope: Applies to thermal insulating products used in building applications; measures increase in deformation over time under constant compressive stress.
- Principle: Compressive creep is determined by monitoring deformation of a specimen between two flat plates while a constant stress is applied at defined temperature and humidity.
- Apparatus: Two flat, self-aligning plates with a controlled loading device; measuring device (e.g., dial gauge or displacement transducer) with accuracy to 0.01 mm; vibration damping and stable support.
- Specimens:
- Dimensions: thickness = original product thickness; recommended square face sizes (50×50 mm up to 300×300 mm).
- Surface flatness/parallelism tolerance: ≤ 0.5 % of side length (max 0.5 mm).
- Number: at least three specimens per stress level (unless product standard specifies otherwise).
- Preparation: cut without altering structure; facings/skins retained if intended for use.
- Conditioning and test environment:
- Standard: (23 ± 2) °C and (50 ± 5) % RH for ≥24 h.
- Tropical alternative: (27 ± 2) °C, (65 ± 5) % RH (must be declared).
- Stress selection: Test at three or more stress levels based on fractions (0.15 to 0.35) of either compressive strength or compressive stress at 10 % strain per ISO 29469.
- Procedure details: Preload options, application time for selected stress, initial deformation recorded at 60 ± 5 s, subsequent deformations recorded at specified times. Calculation methods and linear regression examples are included (Annex A normative, Annex B informative).
- Related documents referenced: ISO 29469 (compression behaviour) and ISO 29768 (linear dimensions of test specimens).
Applications and users
ISO 16534:2020 is used for:
- Quality control and batch testing of building insulation products.
- Product development and comparative performance testing (long‑term deformation under load).
- Certification and compliance testing against product standards.
- Material selection and specification by architects, structural engineers and façade designers to predict serviceability under sustained loads (e.g., under cladding, flooring or mechanical fixings).
Primary users include manufacturers, independent test laboratories, certification bodies, building envelope consultants and standards developers.
Related standards
- ISO 29469 - Determination of compression behaviour (referenced for stress and compression tests).
- ISO 29768 - Determination of linear dimensions of test specimens.
- Prepared in collaboration with CEN/TC 88 (thermal insulating materials and products).