I wonder how many engineers take this into account when designing facades? CEN 12150 (European Standard for toughened glass) states that fritted glass will show around 40% reduction in strength for heat-treated glass; that is 75Mpa vs. 120Mpa¹. The glass industry has worked around and accommodated this weakness for a long time. However, today’s demand for thinner glass and creative uses of glass are bringing this inherent weakness to the forefront. In our mind, the most important fact is that OPACI-COAT-300 Water-based Silicone Spandrel does not weaken the glass. Besides adding fallout protection to a lite of glass, where frit needs a plastic backing, our OPACI-COAT does nothing to disrupt the compression layer in a heat-treated piece of glass.
photo credit www.building.co.uk
How this came to our attention is the amount of phone calls we have gotten where the question of weakening the glass has been asked about our OPACI-COAT products. Come to find out, the industry has known about this for some time. Today, we are seeing thinner and alternate glass manufacturing techniques (Corning’s Gorilla Glass and thinner glass applications in appliances, for example) where the weakness from frit is causing a heck of a lot more problems.
- Ceramic frit weakens toughened glass up to 40% (75Mpa vs. 120Mpa)
- OPACI-COAT-300 Silicone Spandrel does not weaken toughened glass.
- Fallout is achieved with OPACI-COAT-300 without plastic backing.
__ ¹Challenging Glass 3: Conference on Architectural and Structural Applications, June 2012 …edited by Freek Bos, Christian Louter, Rob Nijsse, Fred Vee