Overview
EN ISO 16535:2019 - Thermal insulating products for building applications - Determination of long‑term water absorption by immersion (ISO 16535:2019) specifies procedures and equipment for measuring long‑term water absorption of thermal insulating products. Published by CEN/ISO, it supersedes EN 12087:2013 and defines two principal test methods: Method 1 (partial immersion) to simulate long‑term site exposure, and Method 2 (total immersion) used for specific product assessments. Tests are run over a 28‑day period and are intended for product characterization, quality control and comparative evaluation.
Key Topics and Requirements
- Test methods
- Method 1 - Partial immersion: lower part of specimen in contact with water; excess surface water removed by drainage (1A) or accounted for by initial uptake deduction (1B).
- Method 2 - Total immersion: specimen fully immersed; options include drainage (2A), deduction of initial water uptake (2B) and Archimedes‑principle measurement without moving the sample (2C).
- Test duration: 28 days for both methods.
- Specimen dimensions: prisms with square faces of (200 ± 1) mm; thickness equals original product thickness. Retain skins, facings and coatings.
- Number of specimens: as per product standard or technical specification; otherwise at least four specimens.
- Apparatus and measurement
- Balance with accuracy 0.1 g.
- Water tank with water‑level control to within ±2 mm; specimen restraint must not cover more than 15% of exposed cross‑section.
- Drainage equipment and examples of mesh cages/sinkers are specified.
- Water and temperature: tap water at (23 ± 5) °C; in disputes use deionised water. For tropical conditions the temperature is (27 ± 5) °C - this must be recorded in the test report.
- Preparation and conditioning: specimens must be cut without original edges and prepared without substantially altering product structure.
- Reporting and accuracy: procedures for calculation, expression of results, measurement accuracy and required test report contents are included.
Applications and Who Uses It
- Manufacturers of thermal insulating products for product development, performance claims and quality control.
- Test laboratories performing standardized water absorption testing for compliance and certification.
- Specifiers, architects and engineers assessing material suitability for building envelope, below‑grade or water‑exposed applications.
- Regulatory bodies and certification schemes needing harmonized test data for durability and safety assessments.
Keywords: EN ISO 16535:2019, thermal insulating products, long‑term water absorption, partial immersion, total immersion, building applications, water absorption test.
Related Standards
- ISO 29768 - Determination of linear dimensions of test specimens (referenced).
- Note: EN ISO 16535:2019 replaces EN 12087:2013.
