New construction window scratching is a common problem. Common contributors are surface contaminates such as stucco, dirt (most dirt contains sand) and concrete. Window experts at Read Consulting often are asked to examine scratched windows and determine the cause of scratches. In a majority of cases, the scratches are caused by poor window cleaning practices. This includes using steel blades. The Glass Association of North America (GANA) published Glass Informational Bulletin GANA 01-0300 “Proper Procedures for Cleaning Architectural Glass Products”. In the case of tempered glass windows, a claim is made that stuck on glass particles from the glass temper process become loose and cause the scratching. We have seen one case where there were adhered glass particles. In this case, the windows were properly cleaned, but the clean windows revealed what appeared to be streaks. These windows were not scratched. Microscopic examination of the streaked portions of a representative window revealed the presence of adhered glass (stuck on glass) that aligned in a linear pattern. It was impossible to remove these particles with a metal probe.
Conclusion: In this case adhered particles are unlikely to pop loose and scratch windows if proper window cleaning practices are used.