Overview
ISO 11479-1:2011 – Glass in building - Coated glass - Part 1: Physical defects is an international standard developed by the International Organization for Standardization (ISO) to establish optical quality requirements for coated glass in architectural applications. Focusing specifically on physical defects, this standard applies to glass coatings created through pyrolytic, sol-gel, or vacuum (sputtering) deposition processes. It addresses the needs of manufacturers, architects, and quality control professionals dealing with low-emissivity (low-e) and solar-control coated glass for building glazing. Importantly, ISO 11479-1:2011 is not applicable to patterned or other optically distorting glass types.
Key Topics
ISO 11479-1:2011 outlines a series of critical points for assessing the quality of coated glass intended for buildings:
- Coating Deposition Methods: Covers pyrolytic (applied to hot glass during production), sol-gel (wet coating), and vacuum deposition (sputtering in a vacuum chamber).
- Physical Defects: Defines and addresses various types of coating defects, including:
- Coating rubs (surface abrasion)
- Corrosion (coating degradation)
- Crazing (fine cracks or lines)
- Punctual defects such as spots, pinholes, and scratches
- Stains (irregular, patchy defects larger than punctual defects)
- Defect Detection and Examination:
- Visual inspection in both reflected and transmitted light using daylight or artificial sky illumination
- Defined examination conditions, including proper viewing angles (not exceeding 30° from perpendicular) and designated inspection zones (central and edge areas on both finished and stock sizes)
- Acceptance Criteria:
- Quantitative and qualitative limits for the number and size of defects allowed within specified areas
- Distinction between central and edge zones in terms of permitted defect densities
Applications
ISO 11479-1:2011 is essential for ensuring the optical quality of coated glass used in building façades, windows, and curtain walls. Its main applications include:
- Manufacturing and Quality Control: Glass manufacturers use this standard for product quality assurance, ensuring only glass that meets strict optical standards is supplied for glazing.
- Construction and Architecture: Architects and builders specify ISO 11479-1:2011-compliant glass to assure clients of high-quality, visually appealing installations without unacceptable visible defects.
- Inspection and Certification: Quality inspection professionals rely on its criteria for on-site evaluations and certification processes, reducing the risk of disputes over glass quality in new builds and renovations.
- Enhanced Energy Efficiency: By covering low-e and solar-control coatings, the standard helps projects achieve energy efficiency targets while maintaining visual quality.
Related Standards
For a comprehensive approach to the use of coated glass in buildings, ISO 11479-1:2011 should be used alongside other relevant standards:
- ISO 11479-2 – Glass in building - Coated glass - Part 2: Colour of façade (for assessing appearance and color matching)
- CIE 13.3 Method of measuring and specifying colour rendering properties of light sources (referenced for defining artificial sky conditions in inspections)
- Other glass quality and performance standards such as EN 1096 (Glass in building - Coated glass), and national regulations for safety and performance
By following ISO 11479-1:2011, professionals in the architectural glass and building sectors can ensure transparent quality management, robust defect identification, and confidence in the use of high-performance coated glass products. This leads to both higher customer satisfaction and improved building aesthetics and sustainability.
