Talking Points - Understanding and Explaining the IWCA Bulletin

"IWCA Tempered Glass Informational Bulletin 2004 - Scrapers & Fabricating Debris".

• For decades, scrapers have been used by the window cleaning, glass, and building industries. Many millions of scrapers have been sold by suppliers to these industries, and to homeowners.
   
• Scrapers, which won’t scratch uncoated glass when properly used, have long been the standard and most practical method for removal of debris such as paint, adhesives, or stickers from uncoated glass, not only during construction cleaning, but throughout the useful life of the window.
   
• Scraping is still the most practical method for removing certain types of construction debris.
   
• Scraping is often the only practical method that will yield a perfect result.
   
• Glass scrapers do not scratch uncoated glass when properly used.
   
• Scratched tempered glass has become a major issue in recent years. It has become apparent that most of the problem is due to a microscopic defect called fabricating debris.
   
• Fabricating debris consists mostly of tiny glass chips and glass dust that get baked onto the surface of some tempered glass. These surface defects, also known as glass fines, may create scratches when they are dislodged and trapped by a scraper during window cleaning.
   
• Tempered glass scratches caused by fabricating debris have distinct characteristics, and should not be confused with other types of scratches. Fabricating debris scratches are typically finer and more numerous other common scratches. See the section on Field Identification of Fabricating Debris Scratches.
   
• Window glass in general is more technologically advanced than it was 20 years ago, but fabricating debris on tempered glass is still a quality issue, not a technological advancement.
   
• Fabricating debris is not a theory - it is a fact that even the glass industry does not deny.
   
• The glass industry has taken a new position in recent years - that scrapers should no longer be used to clean glass.
   
• The IWCA's official position was published in June, 2004 - the "IWCA Tempered Glass Informational Bulletin 2004 - Scrapers & Fabricating Debris".
   
• The IWCA advises window cleaners not to accept responsibility for finding fabricating debris defects on tempered glass.
   
• The IWCA recommends testing tempered glass for fabricating debris prior to installation. Builders can test tempered glass when it is delivered, or fabricators can test as part of their quality control program.
   
• Random testing of tempered glass for fabricating debris may confirm the presence of fabricating debris, but can not confirm the absence of fabricating debris on a jobsite.
   
• Thorough testing might involve actually trying to cause fabricating debris scratches on each tempered window with a scraper, using bright lights to locate scratches, and then using magnifiers to confirm that they were fabricating debris scratches. This can take hours, and obviously cannot be done if the objective is to avoid scratching the glass.
   
• The IWCA recommends a tempered glass scratch liability waiver for all construction window cleaning contracts, and for maintenance contracts when significant scraping will be done. This advice is sometimes misunderstood. The builder signs a tempered glass scratch liability waiver to assure that they will not blame the window cleaner for scratches due to fabricating debris on tempered glass, and will not force the window cleaner to prove that fabricating debris caused scratches on tempered glass. The IWCA website - www.iwca.org has an example of a Cleaner to Builder liability waiver.
   
• The IWCA suggests that builders require suppliers to provide quality tempered glass that can be cleaned - without scratching - the same as glass which is not tempered. The IWCA website - www.iwca.org has an example of a Builder to Supplier waiver.
   
• There is never a benefit to fabricating debris, because it makes tempered glass harder to clean and more susceptible to scratching. Builders who realize they have a choice would never choose tempered glass with fabricating debris issues.
   
• When construction window cleaners are asked to use alternative methods instead of scraping, the result is often not satisfactory. And often this only postpones the day that an unsuspecting homeowner or another window cleaner will have to deal with fabricating debris scratches.
   
• If construction window cleaners are asked to reduce scraping to a minimum, they should still require the builder to sign a tempered glass scratch waiver.
   
• Often, reduced scraper use only postpones the day that an unsuspecting homeowner or another window cleaner will have to deal with fabricating debris scratches on poor quality tempered glass.
   
• Plastic scrapers are not recommended. If fabricating debris is present, it may become embedded in the plastic and scratch every window the blade touches from that point on.
   
• Protecting quality glass surfaces during construction is desirable, but protecting poor quality tempered glass will not prevent future problems with fabricating debris scratches.