Overview
ISO 19862:2015 - Buildings and civil engineering works - Sealants - Durability to extension compression cycling under accelerated weathering - defines a laboratory method to classify the durability of exterior sealants used in building construction. The standard specifies how to prepare sealed joint specimens, subject them to cyclic compression and extension while exposed to accelerated weathering (controlled light, water and temperature), and evaluate loss of adhesion or cohesion. Results are used to classify performance of sealants in exterior joints.
Key Topics and Requirements
- Scope: Method for determination and classification of durability of sealants in exterior building joints.
- Test principle: Specimens are cast between two parallel substrates, compressed to a defined width, aged under accelerated weathering, then extended and aged again; observations record adhesion/cohesion loss and whether light transmits through the specimen.
- Specimen preparation: Use substrate materials per ISO 13640 (mortar type 1 or 2). Spacers with cross section 12 mm × 12 mm and anti-adherent backing are used to form the sealant bead.
- Conditioning: Two conditioning options:
- Method A - 28 days at (23 ± 2) °C and (50 ± 10) % RH.
- Method B - alternative conditioning involving oven or water immersion as agreed between parties.
- Apparatus and exposure:
- Fully automated artificial weathering chamber per ISO 4892 series; xenon-arc lamps are the default light source.
- Specified irradiance (xenon-arc default): 550 W/m² (300–800 nm) ±75 W/m²; equivalent settings for 300–400 nm and 340 nm are also specified; irradiance below 300 nm limited to ≤1 W/m².
- Water exposure via spray or immersion (re-circulated water typically ~40 ± 5 °C).
- Tensile test machine to extend specimens at (5.5 ± 0.7) mm/min.
- Evaluation: Record any loss of adhesion/cohesion and translucency; results are reported per the standard’s test report requirements.
Applications and Users
- Who uses it: sealant manufacturers, independent testing laboratories, product certification bodies, façade and cladding specifiers, architects, building envelope consultants, and regulatory authorities.
- Practical value:
- Compare durability of sealant formulations for exterior joints.
- Support product development, quality control and technical data sheets.
- Provide evidence for performance claims, procurement specifications, and regulatory compliance for building envelope materials.
Related Standards
Keywords: ISO 19862:2015, sealants, durability testing, extension compression cycling, accelerated weathering, exterior joints, xenon-arc, sealant classification.